Binding of Isaac: Rebirth Wiki
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Damage Stat Icon Damage refers to the amount of damage each tear deals to enemies, and is represented by a sword. As damage increases, the size of the tears increases as well. However, tear size is not always a direct indication of how much damage tears will do; for example, items like Collectible Dead Onion iconDead Onion and (in Repentance)Collectible Tropicamide iconTropicamide increase tear size without increasing damage. Tears will grow and shrink when damage changes, but tears of a certain size do not have a specific damage value, and two tears of the same size (in two different runs) are likely to have different damage values.

Effective Damage[ | ]

The formula for damage is:

where:

  • CharBaseDmg = The character's base damage multiplied by their multiplier,
  • TotalDmgUps = the total of all regular damage ups collected (not including special exceptions or damage multipliers),
  • FlatDmgUps = the total of all damage ups that are excluded from the above (for example, Curved HornCurved Horn or Collectible Ipecac iconIpecac), and
  • EffectiveDmg = the approximate damage that can be expected per tear, or per 'tick' when using Collectible Brimstone iconBrimstone or Collectible Technology 2 iconTechnology 2.

This formula makes most damage upgrades less potent the more that Isaac has. For example, a Pentagram on Isaac would make his total damage 3.5 * (1 * 1.2 + 1)^0.5 = 3.5 * 1.48 = 5.19. Another Pentagram increases this to 6.45 (a 1.26 increase instead of a 1.69 increase). The higher a character's base damage, the more effective damage ups will be for that character. Flat damage modifiers and special adjustments like Collectible Polyphemus iconPolyphemus or Collectible Sacred Heart iconSacred Heart happen after the main formula.

Character Modifier[ | ]

The character base damage is defined by a base number and a multiplier.

: Collectible Whore of Babylon iconWhore of Babylon has the unique effect of increasing Eve's damage modifier from 0.75 to 1.00 when active. This does not apply to other characters, however.
: Jacob and Esau have -0.75 and +0.25 flat damage, respectively: their base damage, as far as the damage formula is considered, is still 3.5 with a 1.0 multiplier.

Damage Multipliers[ | ]

Some items multiply damage rather than simply adding to it. Damage multipliers do not simply multiply the character's damage once; the damage stat is constantly recalculated and the damage multipliers are multiplied with the end result. This means that if a character starts with 3.50 damage and gets a 2x multiplier, their effective damage will be 3.5*2 = 7.00. If an item that grants +1 damage is picked up, the character's effective damage will be 3.5*(1*1.2+1)^0.5*2 = 3.5*(2.2)^0.5*2 = 3.5*1.48*2 = 10.38, and not 7.00 + 1.

Most damage multipliers stack; for example, (except in Repentance) Collectible Proptosis iconProptosis and Collectible Eve's Mascara iconEve's Mascara both provide a 2x multiplier; picking up both will give a total multiplier of 4x. The exception to this is the 1.5x damage multipliers provided by Collectible Cricket's Head iconCricket's Head, Collectible Magic Mushroom iconMagic Mushroom, and the combination of Collectible Blood of the Martyr iconBlood of the Martyr and Collectible The Book of Belial iconThe Book of Belial. These multipliers do not stack; for example, picking up both Cricket's Head and Magic Mushroom will result in an overall 1.5x multiplier rather than the expected 2.25x.

Reverse Formula[ | ]

Consequently, the reverse formula to determine your damage bonuses from the displayed value is

Multipliers is the product of all damage multipliers in effect.

Items that affect damage[ | ]

Activated Items[ | ]

Name ID Icon Quote Description (in Repentance) Quality
Razor Blade 5.100.126
Razor Blade
Unlimited
Feel my pain Takes one Red HeartHeart of health and grants +1.2 damage for the current room. (in Repentance) Repeated uses in the same room only take half a heart. 0
The Book of Belial 5.100.34
The Book of Belial
3 rooms
Temporary DMG up (in Rebirth) +2 damage for the current room. Passively guarantees a Devil RoomDevil Room or Angel RoomAngel Room will appear while held.
(except in Rebirth) +2 damage for the current room. Passively increases the chance of finding a Devil RoomDevil Room or Angel RoomAngel Room while held.
2
The Nail 5.100.83
The Nail
6 rooms
Temporary demon form (except in Repentance) Gives one Soul HeartSoul Heart. For the current room; +0.7 damage, -0.18 speed, Isaac breaks rocks and deals contact damage.
(in Repentance) Gives half a Black HeartBlack Heart. For the current room; +2 damage, -0.18 speed, Isaac breaks rocks and deals contact damage.
2
(except in Rebirth) D8 5.100.406
D8
4 rooms
Reroll stats Re-rolls Isaac's damage, tears, range, and speed. 2
(in Afterbirth † and Repentance) Dataminer 5.100.481
Dataminer
4 rooms
109 Displaces enemy sprites for the current room, randomly increases one stat and decreases another. 0
(in Afterbirth † and Repentance) Potato Peeler 5.100.487
Potato Peeler
Unlimited
A pound of flesh Removes a Heart Container, increases damage and range, and grants a Collectible Cube of Meat iconCube of Meat. 2
(in Afterbirth † and Repentance) Void 5.100.477
Void
6 rooms
Consume Consumes all pedestal items in the room. Active items will have their effects added to Void, and passive items will grant random stat upgrades. 4
(in Repentance) Berserk! 5.100.704
Berserk!
With damage dealt
Rip and tear Causes Isaac to go berserk for 5 seconds, greatly increasing his speed, tears, and damage, but restricting him to using a melee weapon instead of his tears. This item charges by dealing damage to enemies instead of clearing rooms. 2
(in Repentance) Esau Jr. 5.100.703
Esau Jr.
1 room
Lost brother Swaps between the current character and Esau Jr., who has +2 flat damage and flight. Characters have independent items and health. Dying as either character ends the run. 2
(in Repentance) Golden Razor 5.100.555
Golden Razor
Unlimited
Pain from gain Spends five PennyPennies to increase Isaac's damage by 1.2 for the current room. 1
(in Repentance) Mega Mush 5.100.625
Mega Mush
12 rooms
I'm a big boy now! Gigantifies Isaac for 30 seconds, increasing damage and range while lowering tears, granting invulnerability, and allowing Isaac to crush enemies and obstacles he walks on. The effect persists between rooms. 4
(in Repentance) Sulfur 5.100.556
Sulfur
3 rooms
Temporary demon form Grants Collectible Brimstone iconBrimstone for the current room. 3

Passive Items[ | ]

Name ID Icon Quote Description (in Repentance) Quality
20/20 5.100.245 20/20 Double shot Isaac fires two tears at once, one from each eye. (in Repentance) 0.8x damage multiplier. 4
A Lump of Coal 5.100.132 A Lump of Coal My Xmas present The more distance tears travel, the more damage they will do. 3
Abaddon 5.100.230 Abaddon Evil + DMG up + fear shot (except in Repentance) +1.5 damage, +0.2 speed. Removes all Red Heart containers, grants six Black HeartBlack Hearts, and adds a chance to shoot fear tears.
(in Repentance) +1.5 damage, +0.2 speed. Grants two Black HeartBlack Hearts, converts all Red Heart Containers into Black Hearts, and adds a chance to shoot fear tears.
3
Blood Clot 5.100.254 Blood Clot DMG + range up (except in Repentance)Tears fired from the left eye have +1 flat damage, +5 range, and +0.5 tear falling speed.
(in Repentance)Tears fired from the left eye have +1 flat damage and +2.75 range.
2
Blood of the Martyr 5.100.7 Blood of the Martyr DMG up +1 damage. Isaac shoots blood tears. 3
Bloody Lust 5.100.157 Bloody Lust RAGE! Increases Isaac's damage whenever he takes damage, up to six times. The bonus resets when entering a new floor. 2
Brimstone 5.100.118 Brimstone Blood laser barrage Tears are replaced by a laser beam that pierces through all enemies and obstacles in its path and deals high damage. Can only be fired after a short charge-up period. 4
Capricorn 5.100.307 Capricorn All stats up (except in Repentance) Adds 1 Red Heart Container, gives +0.5 Damage, +0.1 Speed, +1.5 Range, and -1.0 Tear Delay, and gives 1 BombBomb, PennyPenny, and KeyKey.
(in Repentance) Adds 1 Red Heart Container, gives +0.5 Damage, +0.1 Speed, +0.75 Range, and +0.5 Fire Rate, and gives 1 BombBomb, PennyPenny, and KeyKey.
3
Cat-o-nine-tails 5.100.165 Cat-o-nine-tails Shot speed + damage up +1 damage, +0.23 shot speed. 3
Ceremonial Robes 5.100.216 Ceremonial Robes DMG + evil up Grants 3 Black HeartBlack Hearts, and +1 damage. 3
Champion Belt 5.100.208 Champion Belt DMG + challenge up +1 damage. Increases the chance of champion enemies appearing by 15%. 3
Charm of the Vampire 5.100.62 Charm of the Vampire DMG up + kills heal Heals Isaac for a Half Red HeartHalf Red Heart for every 13 enemies killed. (in Repentance) +0.3 damage. 1
Chemical Peel 5.100.154 Chemical Peel DMG up Tears fired from the left eye have +2 flat damage. 2
Cricket's Head 5.100.4 Cricket's Head DMG up Increases Damage by 0.5, and increases damage multiplier by x1.5. 4
Dark Matter 5.100.259 Dark Matter DMG up + fear shot +1 damage, adds a chance to shoot fear tears. 3
Death's Touch 5.100.237 Death's Touch Piercing shots + DMG up +1.5 damage, -0.3 tears. Tears are replaced with large piercing scythes. 3
Eve's Mascara 5.100.310 Eve's Mascara DMG up, tears + shot speed down (except in Repentance) Doubles damage, halves tears stat, and greatly reduces shot speed.
(in Repentance) Doubles damage, 0.66x tears multiplier, and greatly reduces shot speed.
3
Experimental Treatment 5.100.240 Experimental Treatment Some stats up, some stats down (in Rebirth and Afterbirth) Randomly increases and decreases some of Isaac's stats.
(in Afterbirth † and Repentance) Increases four random stats and decreases the other two.
1
Godhead 5.100.331 Godhead God tears (except in Repentance) Grants homing tears with a damaging halo. +0.5 Damage, -0.3 Tears -0.3 Shot Speed, +0.8 Tear Falling Speed, and +1.2 Range.
(in Repentance) Grants homing tears with a damaging halo. +0.5 Damage, -0.3 Tears, and -0.3 Shot Speed.
4
Growth Hormones 5.100.70 Growth Hormones Speed + DMG up (except in Repentance) +1 damage, +0.4 speed.
(in Repentance) +1 damage, +0.2 speed.
3
Guillotine 5.100.206 Guillotine DMG + tears up. An out-of-body experience! Isaac's head is removed from his body and floats around him as an orbital. (except in Repentance) Gives +1 damage and grants -1 tear delay. (in Repentance) Gives +1 damage and grants +0.5 fire rate. 2
Ipecac 5.100.149 Ipecac Explosive shots Replaces tears with explosive and poisoning projectiles fired in an arc from the mouth. 4
Iron Bar 5.100.201 Iron Bar DMG up + concussive tears +0.3 damage. Adds a chance to shoot concussive tears, causing enemies to walk around randomly. 2
Jesus Juice 5.100.197 Jesus Juice Damage + range up (except in Repentance) +0.5 damage, +0.25 range, +0.5 tear falling speed.
(in Repentance) +0.5 damage, +1.5 range.
2
Libra 5.100.304 Libra You feel balanced Gives 6 PennyCoins, 6 BombBombs, and 6 KeyKeys and balances out all attributes. 1
Magic Mushroom 5.100.12 Magic Mushroom All stats up! Makes Isaac bigger. Adds one Red Heart Container, +0.3 Damage, x1.5 damage multiplier, (except in Repentance) +5.25 / (in Repentance) +2.5 Range, and +0.3 Speed, and restores all Health. 4
MEAT! 5.100.193 MEAT! DMG + HP up Grants one full Red Heart container, +0.3 damage. (in Repentance) Heals 1 additional Red HeartRed Heart 2
Missing No. 5.100.258 Missing No. Syntax error Randomizes all passive items and stats upon pickup and at the start of each succeeding floor. 0
My Reflection 5.100.5 My Reflection Boomerang tears + DMG up + luck down Gives Isaac's tears a boomerang effect. (except in Repentance) +1.5 range, +1 tear falling speed, x1.6 shot speed multiplier. (in Repentance) 2x + 1.5 range, +1.5 damage, -1 luck, 1.6x shot speed multiplier. 2
Odd Mushroom 5.100.121 Odd Mushroom HP + DMG up, speed down (except in Repentance) Grants one empty Heart container, +0.3 damage, +0.25 range, +0.5 tear falling speed, and -0.1 speed.
(in Repentance) Grants one full Heart container, +1 damage, +1.5 range, and -0.2 speed
2
Odd Mushroom 5.100.120 Odd Mushroom Tears + speed up, DMG down +1.7 tears, +0.3 speed, slightly reduces damage. 2
Pentagram 5.100.51 Pentagram DMG up +1 damage, increases Devil RoomDevil Room / Angel RoomAngel Room chance by 10%. 3
Polyphemus 5.100.169 Polyphemus Mega tears Isaac fires huge tears that deal massive damage, but fire rate is greatly decreased. If a tear kills an enemy, it travels on with any leftover damage. 4
Proptosis 5.100.261 Proptosis Short range mega tears Tears start out massive with high damage, and then shrink down and become weaker over a short range. 3
Sacred Heart 5.100.182 Sacred Heart Homing shots + DMG up (except in Repentance) Adds a Red Heart Container. Grants homing tears, a x2.3 Damage multiplier, +1 flat Damage, -0.4 Tears, -0.25 Shot Speed, and +4.125 Range.
(in Repentance) Adds a Red Heart Container. Grants homing tears, a x2.3 Damage multiplier, +1 flat Damage, -0.4 Tears, and -0.25 Shot Speed.
4
SMB Super Fan 5.100.189 SMB Super Fan All stats up (except in Repentance) +1 Red Heart container, +0.3 damage, +0.2 tears, +0.2 speed, +0.5 range, +1 tear falling speed. Fully restores all red hearts.
(in Repentance) +1 Red Heart container, +0.3 damage, +0.2 tears, +0.2 speed, +2.5 range. Fully restores all red hearts.
3
Soy Milk 5.100.330 Soy Milk DMG down + tears way up Tears are smaller and do much less damage, but fire in very rapid succession. 2
Steven 5.100.50 Steven DMG up +1 damage. 3
Stigmata 5.100.138 Stigmata DMG + HP up +0.3 damage, grants one full Red Heart container. (in Repentance) Heals 1 additional Red HeartRed Heart. 2
Synthoil 5.100.345 Synthoil DMG + range up (except in Repentance) +1 damage, +5.25 range, +0.5 tear falling speed.
(in Repentance) +1 damage, +2.5 range.
3
Technology 2 5.100.152 Technology 2 Extra laser Replaces the tears fired from Isaac's right eye with a rapid-firing low damage piercing laser. (except in Repentance) Damage down. 2
The Halo 5.100.101 The Halo All stats up (except in Repentance) Grants one full Red Heart container, +0.3 damage, +0.2 tears, +0.25 range, +0.3 speed, and +0.5 tear falling speed.
(in Repentance) Grants one full Red Heart container, +0.3 damage, +0.2 tears, +1.5 range, and +0.3 speed. Heals 1 additional Red HeartRed Heart.
2
The Mark 5.100.79 The Mark DMG + speed up (except in Repentance) Grants one Soul HeartSoul Heart, +1 damage, and +0.2 speed.
(in Repentance) Grants one Black HeartBlack Heart, +1 damage, and +0.2 speed.
3
The Negative 5.100.328 The Negative Fate chosen If Isaac has half a red heart or no red hearts after taking damage, all enemies in the room take significant damage. Allows entrance into the Dark RoomDark Room. (in Repentance) +1 Damage and also allows access to HomeHome. 2
The Pact 5.100.80 The Pact DMG + tears up (except in Repentance) Grants two Soul HeartSoul Hearts, +0.5 damage, and +0.7 tears.
(in Repentance) Grants two Black HeartBlack Hearts, +0.5 damage, and +0.7 tears.
3
The Peeper 5.100.155 The Peeper Plop! Spawns a familiar that slowly floats around the room in a zig-zag pattern, damaging enemies it passes through. (in Repentance) Increases the damage of tears from Isaac's left eye by 35%. 2
The Small Rock 5.100.90 The Small Rock DMG up + speed down +1 damage, +0.2 tears, -0.2 speed. 3
Whore of Babylon 5.100.122 Whore of Babylon Curse up Grants +1.5 Damage and +0.3 Speed whenever Isaac has a Half Red HeartHalf Red Heart or less. 2
(except in Rebirth) 8 Inch Nails 5.100.359 8 Inch Nails Stick it to 'em! +1.5 damage. Replaces Isaac's tears with nails, which have increased knockback. 3
(except in Rebirth) Crown Of Light 5.100.415 Crown Of Light The untainted gain power +2 Soul HeartSoul Hearts. While Isaac has no empty red hearts, grants 2x damage, increased range, and -0.3 shot speed. Regardless of health, the crown deactivates for the current room when Isaac takes damage. 4
(except in Rebirth) Dead Eye 5.100.373 Dead Eye Accuracy brings power! Isaac's damage increases each time an enemy is hit. Damage is reset upon missing a shot. 3
(except in Rebirth) Lusty Blood 5.100.411 Lusty Blood Their blood brings rage! Isaac's damage increases for the current room each time he kills an enemy. 3
(except in Rebirth) Maw Of The Void 5.100.399 Maw Of The Void Consume thy enemy! Charged by firing for 2.5 seconds and when released, creates a black ring around Isaac that rapidly deals damage. (except in Repentance) +1 damage, the ring can cause enemies to drop Black HeartBlack Hearts. 3
(except in Rebirth) Purity 5.100.407 Purity Aura stat boost Boosts one of Isaac's stats depending on the color of the aura around him. The aura disappears upon taking damage and reappears with a random color upon entering a new room. Red boosts damage, blue boosts tears, yellow boosts speed, and orange boosts range. 3
(except in Rebirth) Succubus 5.100.417 Succubus Damage booster Spawns a flying familiar that bounces around the room with a black aura, dealing rapid damage to any enemies inside it. While standing in the aura, Isaac gains a 1.5x tear damage multiplier. 3
(in Afterbirth † and Repentance) Adrenaline 5.100.493 Adrenaline Panic = power Increases damage based on how many empty Red Heart containers Isaac has. 2
(in Afterbirth † and Repentance) Bozo 5.100.513 Bozo Party time! +0.1 flat damage, grants a Soul HeartSoul Heart. Enemies can randomly become briefly charmed or feared. Taking damage has a chance to spawn a Rainbow PoopRainbow Poop. 2
(in Afterbirth † and Repentance) Camo Undies 5.100.497 Camo Undies Camo kid Isaac becomes camouflaged at the beginning of each room. Until he shoots, all non-boss enemies will be confused. (in Repentance) Isaac gains +0.5 Speed while camouflaged, and gains Tears and Damage upon breaking it. 3
(in Afterbirth † and Repentance) Death's List 5.100.530 Death's List Just hope you're not next... Grants a pickup or stat upgrade if all enemies in a room are killed in the order they are marked. 2
(in Afterbirth † and Repentance) Dog Tooth 5.100.445 Dog Tooth Bark at the moon! +0.3 damage, +0.1 speed. Plays a howl or bark sound when entering a room with undiscovered Secret RoomSecret Rooms or Crawl SpaceCrawl Spaces. 2
(in Afterbirth † and Repentance) Haemolacria 5.100.531 Haemolacria I'm seeing red... Tears are now fired in an arc. Upon hitting the floor, an obstacle, or an enemy, they burst into many smaller tears in all directions. Increases tear delay. 4
(in Afterbirth † and Repentance) Hallowed Ground 5.100.543 Hallowed Ground Portable sanctuary Spawns a white poop familiar, which turns into a White PoopWhite Poop when Isaac is hurt. White poop has an aura that increases tear fire rate and can block enemy shots. (in Repentance) The aura also increases damage by 20% and gives homing. 1
(in Afterbirth † and Repentance) Sulfuric Acid 5.100.463 Sulfuric Acid Acid tears! +0.3 damage. Adds a chance to fire acidic tears which can destroy obstacles and open doors. 2
(in Repentance) Almond Milk 5.100.561 Almond Milk DMG down + tears up + you feel nutty Quadruples fire rate, with x0.3 damage multiplier. Each tear is a given random effect that alters its movement. 1
(in Repentance) Binge Eater 5.100.664 Binge Eater All you can eat +1 Red Heart Container and fully heals Isaac. Item pedestals also offer a random food item. Picking up a food item temporarily grants +3.6 damage and permanently boosts 2 stats. 4
(in Repentance) Blood Oath 5.100.569 Blood Oath Bleed me dry Stabs Isaac at the beginning of each floor, draining his Red HeartRed Hearts. Increases damage and speed for the floor based on the amount drained. 1
(in Repentance) Candy Heart 5.100.671 Candy Heart Power of love Gives Isaac a permanent stat boost whenever he heals with Red HeartRed Heart pickups. 1
(in Repentance) Consolation Prize 5.100.644 Consolation Prize +1 to lowest stat Increases Isaac's lowest stat and drops either 3 PennyCoins, 1 BombBomb, or 1 KeyKey depending on what Isaac has the least of. 1
(in Repentance) Dogma 5.100.633 Dogma Ascended Grants flight, +2 damage, and increases speed to 1.1. Grants enough health to have 6 full hearts, if possible. Grants the Collectible Holy Mantle iconHoly Mantle effect for the room it was obtained in. Automatically given to Isaac after defeating Dogma. 3
(in Repentance) Eye of the Occult 5.100.572 Eye of the Occult DMG up + range up + controlled tears +1 damage, +2 range, -0.16 shot speed. Isaac's tears can be controlled mid-flight with tear controls. 3
(in Repentance) False PHD 5.100.654 False PHD Worse pills + evil up Converts good pills into bad pills and identifies all pills. Bad pills now have secondary positive effects. Grants one Black HeartBlack Heart. 2
(in Repentance) Glass Eye 5.100.730 Glass Eye DMG + luck up +0.75 damage, +1 luck. 3
(in Repentance) Heartbreak 5.100.694 Heartbreak Eternal sorrow Grants 3 broken hearts and +0.25 damage for every broken heart Isaac has. Every otherwise fatal hit will add 2 more until Isaac has nothing but broken hearts. 3
(in Repentance) Immaculate Heart 5.100.573 Immaculate Heart Halo of tears Adds one Red Heart Container and fully restores health. x1.2 damage multiplier. Isaac will occasionally fire extra tears that orbit around him. 3
(in Repentance) Keeper's Sack 5.100.716 Keeper's Sack Spending power Gives range, speed, or damage when buying things from a shop. Also spawns three coins and a KeyKey on pickup. 3
(in Repentance) Mom's Ring 5.100.732 Mom's Ring DMG up +1 Damage. Drops a random Rune or Soul Stone upon pickup. 3
(in Repentance) Red Stew 5.100.621 Red Stew Full HP + temporary DMG up Refills all heart containers. Grants an enormous damage boost that wears off over time. 2
(in Repentance) Redemption 5.100.673 Redemption Deliver me from evil If Isaac enters a Devil RoomDevil Room, but leaves without taking/opening anything in it (including Black HeartBlack Hearts, etc.), he gets +1 Damage and a Soul HeartSoul Heart at the start of the next floor. 2
(in Repentance) Sanguine Bond 5.100.692 Sanguine Bond He awaits your offering Spawns a special set of spikes in the Devil RoomDevil Room. Taking damage from the spikes has a chance to grant a reward. 1
(in Repentance) Sausage 5.100.669 Sausage All stats up Adds a Red Heart Container, fully heals Isaac, and gives +0.2 Speed, +0.5 Damage, +0.5 Tears, +2.5 Range, +0.2 Shot Speed, and +1.0 Luck. Increases the chance of encountering a Devil RoomDevil Room, Angel RoomAngel Room, and/or PlanetariumPlanetarium each by 6.9%. 3
(in Repentance) Sol 5.100.588 Sol Radiant victory Reveals the location of the Boss RoomBoss Room. Upon defeating a boss, activates XIX - The SunXIX - The Sun, fully recharges Isaac's active item, grants bonus damage and luck for the rest of the floor, and removes curses. 2
(in Repentance) Soul Locket 5.100.686 Soul Locket Power of faith Gives Isaac a permanent stat boost whenever he picks up a Soul HeartSoul Heart. 1
(in Repentance) Stapler 5.100.708 Stapler DMG up +1 Damage. Prevents Isaac from firing tears from his left eye, like Character Cain iconCain. 3
(in Repentance) Star of Bethlehem 5.100.651 Star of Bethlehem Follow the light Spawns a star familiar that slowly travels towards the Boss RoomBoss Room, giving an aura that increases damage and tears and grants homing tears. 3
(in Repentance) Stye 5.100.731 Stye DMG + range up Tears fired from Isaac's right eye have +28% Damage, +6.5 Range, and -0.3 Shot Speed. 2
(in Repentance) Terra 5.100.592 Terra Born to rock +1 Damage. Replaces tears with rocks that deal variable damage, have increased knockback, and can destroy obstacles. 3

Trinkets[ | ]

Name ID Icon Quote Description
Curved Horn 5.350.35 Curved Horn DMG up +2 flat damage.
Red Patch 5.350.40 Red Patch Your rage grows Grants a chance to gain +1.8 damage for the current room upon taking damage.
Samson's Lock 5.350.58 Samson's Lock Your rage grows 1/15 chance to gain +0.5 damage for the current room each time an enemy dies.
(except in Rebirth) Black Feather 5.350.80 Black Feather With darkness comes power Increases Isaac's Damage for each 'evil' item or trinket he possesses.
(in Afterbirth † and Repentance) Cracked Crown 5.350.92 Cracked Crown Stat booster (except in Repentance) Decreases Isaac's tear delay by 20%, and improves the effectiveness of his other stat upgrades by 33%.
(in Repentance) Improves the effectiveness of stat upgrades by 20%.
(in Afterbirth † and Repentance) Dim Bulb 5.350.101 Dim Bulb I think it's broken Provides a boost to all stats when Isaac's active item is completely uncharged.
(in Afterbirth † and Repentance) Vibrant Bulb 5.350.100 Vibrant Bulb It needs power Provides a boost to all stats when Isaac's active item is fully charged.

Cards and Runes[ | ]

Name ID Icon Message Description
III - The Empress 5.300.4 III - The Empress May your rage bring power Triggers the Collectible Whore of Babylon iconWhore of Babylon effect (+1.5 Damage, +0.3 Speed) for the current room, regardless of Isaac's health total.
XI - Strength 5.300.12 XI - Strength May your power bring rage Grants the effects of Collectible Magic Mushroom iconMagic Mushroom (minus the health restoration) for one room. The added Red Heart container is not removed if doing so would kill Isaac.
XV - The Devil 5.300.16 XV - The Devil Revel in the power of darkness Grants Isaac a temporary +2 increase to Damage for the current room (same effect as Collectible The Book of Belial iconThe Book of Belial).
(in Afterbirth † and Repentance) Black Rune 5.300.41 Black Rune Void Deals 40 damage to all enemies in the room. Consumes all pickups in the room and turns them into Blue Flies and Spiders. Consumes all pedestal items in the room and turns them into random stat upgrades. No effect on ShopShop or Devil RoomDevil Room items. (Essentially, activates Collectible The Necronomicon iconThe Necronomicon, Collectible Compost iconCompost, and Collectible Void iconVoid).
(in Afterbirth † and Repentance) Huge Growth 5.300.52 Huge Growth Become immense! (except in Repentance) For the current room, makes Isaac larger, allows him to crush obstacles he walks on, and grants +7 flat Damage and +30 Range.
(in Repentance) For the current room, makes Isaac larger, allows him to crush obstacles he walks on, and grants +7 flat Damage and +3 Range.
(in Repentance) XIX - The Sun? 5.300.75 XIX - The Sun? May the darkness swallow all around you Gain Collectible Spirit of the Night iconSpirit of the Night and +1.5 Damage for the current floor. Turns Isaac's Red Hearts into Bone Hearts, but they revert once the effect ends. Also causes Curse of DarknessCurse of Darkness that cannot be dispelled.
(in Repentance) Soul of Judas 5.300.84 Soul of Judas Right behind you Stops time for 3 seconds and invokes Collectible Dark Arts iconDark Arts, turning Isaac into a phantom that can pass through enemies to paralyze them, then attack them for quickly increasing chained damage and damage bonuses.
(in Repentance) Soul of Samson 5.300.87 Soul of Samson Slay a thousand Isaac turns berserk (similar to using Collectible Berserk! iconBerserk!) for 10 seconds, gaining +0.4 Speed, some Tears and +3 flat Damage along with his melee attack.

Items that multiply damage[ | ]

Positive Multiplier[ | ]

Name ID Icon Quote Description (in Repentance) Quality
Cricket's Head 5.100.4 Cricket's Head DMG up Increases Damage by 0.5, and increases damage multiplier by x1.5. 4
Eve's Mascara 5.100.310 Eve's Mascara DMG up, tears + shot speed down (except in Repentance) Doubles damage, halves tears stat, and greatly reduces shot speed.
(in Repentance) Doubles damage, 0.66x tears multiplier, and greatly reduces shot speed.
3
Magic Mushroom 5.100.12 Magic Mushroom All stats up! Makes Isaac bigger. Adds one Red Heart Container, +0.3 Damage, x1.5 damage multiplier, (except in Repentance) +5.25 / (in Repentance) +2.5 Range, and +0.3 Speed, and restores all Health. 4
Polyphemus 5.100.169 Polyphemus Mega tears Isaac fires huge tears that deal massive damage, but fire rate is greatly decreased. If a tear kills an enemy, it travels on with any leftover damage. 4
Sacred Heart 5.100.182 Sacred Heart Homing shots + DMG up (except in Repentance) Adds a Red Heart Container. Grants homing tears, a x2.3 Damage multiplier, +1 flat Damage, -0.4 Tears, -0.25 Shot Speed, and +4.125 Range.
(in Repentance) Adds a Red Heart Container. Grants homing tears, a x2.3 Damage multiplier, +1 flat Damage, -0.4 Tears, and -0.25 Shot Speed.
4
(except in Rebirth) Crown Of Light 5.100.415 Crown Of Light The untainted gain power +2 Soul HeartSoul Hearts. While Isaac has no empty red hearts, grants 2x damage, increased range, and -0.3 shot speed. Regardless of health, the crown deactivates for the current room when Isaac takes damage. 4
(except in Rebirth) Dead Eye 5.100.373 Dead Eye Accuracy brings power! Isaac's damage increases each time an enemy is hit. Damage is reset upon missing a shot. 3
(except in Rebirth) Succubus 5.100.417 Succubus Damage booster Spawns a flying familiar that bounces around the room with a black aura, dealing rapid damage to any enemies inside it. While standing in the aura, Isaac gains a 1.5x tear damage multiplier. 3
(in Afterbirth † and Repentance) Haemolacria 5.100.531 Haemolacria I'm seeing red... Tears are now fired in an arc. Upon hitting the floor, an obstacle, or an enemy, they burst into many smaller tears in all directions. Increases tear delay. 4
(in Afterbirth † and Repentance) Hallowed Ground 5.100.543 Hallowed Ground Portable sanctuary Spawns a white poop familiar, which turns into a White PoopWhite Poop when Isaac is hurt. White poop has an aura that increases tear fire rate and can block enemy shots. (in Repentance) The aura also increases damage by 20% and gives homing. 1
(in Repentance) Immaculate Heart 5.100.573 Immaculate Heart Halo of tears Adds one Red Heart Container and fully restores health. x1.2 damage multiplier. Isaac will occasionally fire extra tears that orbit around him. 3
(in Repentance) Star of Bethlehem 5.100.651 Star of Bethlehem Follow the light Spawns a star familiar that slowly travels towards the Boss RoomBoss Room, giving an aura that increases damage and tears and grants homing tears. 3

Character-specific damage multipliers:

  • Character Eve iconEve + Collectible Whore of Babylon iconWhore of Babylon - Raises her damage multiplier from 0.75x to 1x while the whore effect is active. (It does not have this effect for any other character.)
  • Character Judas iconJudas + Collectible The Book of Belial iconThe Book of Belial + (in Repentance)Collectible Birthright iconBirthright + (in Repentance)Collectible Damocles iconDamocles - 1.4x damage multiplier while the Damocles effect is active.
  • Dying with Collectible Judas' Shadow iconJudas' Shadow transforms the player into Character Dark Judas iconDark Judas, who has a 2x damage multiplier, which is the highest character-based damage multiplier in the game.

Synergy-specific damage multipliers:

Random Multiplier[ | ]

Name ID Icon Quote Description (in Repentance) Quality
(except in Rebirth) D8 5.100.406
D8
4 rooms
Reroll stats Re-rolls Isaac's damage, tears, range, and speed. 2

Negative Multiplier[ | ]

Name ID Icon Quote Description (in Repentance) Quality
20/20 5.100.245 20/20 Double shot Isaac fires two tears at once, one from each eye. (in Repentance) 0.8x damage multiplier. 4
Odd Mushroom 5.100.120 Odd Mushroom Tears + speed up, DMG down +1.7 tears, +0.3 speed, slightly reduces damage. 2
Soy Milk 5.100.330 Soy Milk DMG down + tears way up Tears are smaller and do much less damage, but fire in very rapid succession. 2
Technology 2 5.100.152 Technology 2 Extra laser Replaces the tears fired from Isaac's right eye with a rapid-firing low damage piercing laser. (except in Repentance) Damage down. 2
(in Repentance) Almond Milk 5.100.561 Almond Milk DMG down + tears up + you feel nutty Quadruples fire rate, with x0.3 damage multiplier. Each tear is a given random effect that alters its movement. 1
  • Note that Collectible Odd Mushroom (Thin) iconOdd Mushroom is not a "real" damage multiplier in that it only affects the increases from other items. For example, if you only had Collectible Eve's Mascara iconEve's Mascara for a 2x damage multiplier and nothing else, then Odd Mushroom would only grant a flat -0.4 damage (because nothing would be multiplied by 0.9).

(in Repentance) The order that damage multipliers and flat damage are applied[ | ]

Order Item Damage Notes
0 Any normal damage up not listed below
1 Collectible Odd Mushroom (Thin) iconOdd Mushroom TotalDmgUps * 0.9 The normal damage ups below this don't get this multiplier
2 Collectible Odd Mushroom (Thin) iconOdd Mushroom -0.4
Black FeatherBlack Feather +0.5 per evil item
Collectible Camo Undies iconCamo Undies +10.5 Fades quickly over time
Collectible Dark Arts iconDark Arts +1 per enemy/bullet Fades over time
Collectible Golden Razor iconGolden Razor +1.2
Character Lazarus Risen iconLazarus Risen +0.5 Permanent damage up from reviving
Collectible Lusty Blood iconLusty Blood +0.5 per enemy up to 5 max Both items share the same max
Samson's LockSamson's Lock
Collectible The Nail iconThe Nail +2
Collectible Purity iconPurity +4 With damage aura
Collectible Razor Blade iconRazor Blade +1.2
Red PatchRed Patch +1.8
3 Collectible Polyphemus iconPolyphemus flat +4 These don't stack with each other
Collectible Polyphemus iconPolyphemus + Collectible 20 20 icon20/20/Collectible The Inner Eye iconThe Inner Eye/Collectible Mutant Spider iconMutant Spider flat +5
4 Collectible Polyphemus iconPolyphemus x2 This doesn't apply with Collectible 20 20 icon20/20/Collectible The Inner Eye iconThe Inner Eye/Collectible Mutant Spider iconMutant Spider
Character multiplier See above section
5 Character flat damage See above section
Collectible Esau Jr. iconEsau Jr. flat +2
6 Collectible Mega Mush iconMega Mush x4
7 Collectible Berserk! iconBerserk! flat +3
Collectible Bozo iconBozo flat +0.1
Collectible Candy Heart iconCandy Heart flat +0.1
Collectible Consolation Prize iconConsolation Prize flat +1
Curved HornCurved Horn flat +2
Collectible Dataminer iconDataminer flat +1 or -1
Collectible Death's List iconDeath's List flat +1
Collectible Experimental Treatment iconExperimental Treatment flat +1 or -1
Character The Forgotten iconThe Forgotten + Mom's Knife flat +4
Huge GrowthHuge Growth flat +7
Collectible Missing No. iconMissing No. flat +1 or -1
Collectible Potato Peeler iconPotato Peeler flat +0.2
Collectible Soul Locket iconSoul Locket flat +0.2
Collectible Void iconVoid flat +1
8 Collectible Brimstone iconBrimstone x2 x1.2 Doesn't apply to Collectible Haemolacria iconHaemolacria and overrides Collectible Brimstone iconBrimstone + Collectible Technology iconTechnology
Collectible Crown Of Light iconCrown Of Light x2
Collectible Sacred Heart iconSacred Heart x2.3
9 Collectible Sacred Heart iconSacred Heart flat +1
10 Character Judas iconJudas + Collectible Birthright iconBirthright + Collectible Damocles iconDamocles x1.4
11 Character Judas iconJudas + Collectible Birthright iconBirthright + Collectible Damocles iconDamocles flat +1
12 Collectible Hallowed Ground iconHallowed Ground x1.2 These don't stack with each other
Collectible Immaculate Heart iconImmaculate Heart
Collectible Star of Bethlehem iconStar of Bethlehem
13 Collectible Adrenaline iconAdrenaline flat ((2 * MissingHearts) ^ 1.6) * 0.1
Collectible Bloody Lust iconBloody Lust flat +6 max
14 Character Azazel iconAzazel + Collectible The Ludovico Technique iconThe Ludovico Technique x0.5
Collectible Brimstone iconBrimstone + Collectible Technology iconTechnology x1.5 These don't stack with each other
Collectible Haemolacria iconHaemolacria
15 Collectible Ipecac iconIpecac flat +40 These don't stack with each other
Collectible Ipecac iconIpecac + Collectible Brimstone iconBrimstone / Collectible Dr. Fetus iconDr. Fetus / Character The Forgotten iconThe Forgotten / Collectible The Ludovico Technique iconThe Ludovico Technique / Collectible Mom's Knife iconMom's Knife / Collectible Tech X iconTech X / Collectible Technology iconTechnology flat +2
16 Collectible 20 20 icon20/20 x0.8
Collectible Almond Milk iconAlmond Milk x0.3
Collectible Cricket's Head iconCricket's Head x1.5 These don't stack with each other
Collectible Magic Mushroom iconMagic Mushroom
Collectible The Book of Belial iconThe Book of Belial + Collectible Blood of the Martyr iconBlood of the Martyr
Collectible D8 iconD8 x0.5 to x2.0
Collectible Dead Eye iconDead Eye x2 max
Collectible Eve's Mascara iconEve's Mascara x2
Collectible Soy Milk iconSoy Milk x0.2 Overridden by Almond Milk
Collectible Star of Bethlehem iconStar of Bethlehem x1.5
Collectible Succubus iconSuccubus x1.5
17 Cracked CrownCracked Crown x1.2 for damage over 3.5

Other[ | ]


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