Binding of Isaac: Rebirth Wiki

Added in Repentance

Modeling Clay is an unlockable trinket added in The Binding of Isaac: Repentance.


  • Has a 50% chance to mimic the effect of a random passive item from the current room’s item pool when entering a room.


  • Modeling Clay can only mimic items that have the "summonable" item tag, the same way Lemegeton Lemegeton selects the wisps it summons.
  • The item given by Modeling Clay is locked within any given room.
  • Items that would give or remove consumables or heart containers will not do so if Modeling Clay mimics them.
  • If Isaac holds multiple copies of Modeling Clay, they will all mimic the same item.
    • Note: This will not give multiple copies of the item, Isaac will only receive one copy.


  • Chaos Chaos: Removes the room pool constraint for Modeling Clay's available items.
  • Sacrificial Altar Sacrificial Altar: If Modeling Clay is currently mimicking a viable familiar, it will also be sacrificed and spawn an additional Devil Room item, but Modeling Clay will not be destroyed.
  • TMTRAINER TMTRAINER: Modeling Clay cannot copy glitched items; it will do nothing and not have a sprite if it tries to.

If Modeling Clay mimics the following items, they will behave in the following ways:

  • 9 Volt 9 Volt: 1-room charge active items will not recharge over time. Other active items are affected normally.
  • Belly Button Belly Button / Mom's Purse Mom's Purse: Allows Isaac to hold another trinket alongside Modeling Clay if he picks it up while Modeling Clay mimics the item, and he will continue to hold both even after Modeling Clay changes. If Isaac tries to pick up another trinket while he already has two, it will instead be destroyed and he will only be able to hold one trinket again.
    • Isaac can safely exchange cards/pills/trinkets by manually dropping them, at the cost of being unable to hold two.
    • Extra trinkets held this way are susceptible to not working properly, if at all.
  • Black Candle Black Candle: Does not remove the current floor’s curse.
  • Bloody Lust Bloody Lust / Bloody Gust Bloody Gust / False PHD False PHD / Keeper's Sack Keeper's Sack / Rock Bottom Rock Bottom: Stat boosts will not persist after Modeling Clay changes. If it mimics that item again, it will remember the stat boosts they gave.
  • Blue Map Blue Map / The Compass The Compass / The Mind The Mind / Treasure Map Treasure Map: Does not reveal rooms on the map.
  • Candy Heart Candy Heart / Soul Locket Soul Locket: Stats granted from picking up hearts will persist after Modeling Clay changes.
  • Cambion Conception Cambion Conception / Immaculate Conception Immaculate Conception: If Isaac can somehow meet the requirements for these items to spawn familiars, the familiars will persist for only one room after Modeling Clay changes.
  • Delirious Delirious / Mr. ME! Mr. ME!: Has no effect, even if Isaac uses his active item.
  • Dog Tooth Dog Tooth / Spelunker Hat Spelunker Hat / X-Ray Vision X-Ray Vision / YO LISTEN! YO LISTEN!: Will reveal/open neighboring Secret Rooms.
  • False PHD False PHD / PHD PHD: Pills’ effects will be changed, but they will not be identified.
  • GB Bug GB Bug: The familiar respawns every time the trinket mimics the item.
  • Glitched Crown Glitched Crown: Items that are spawned while it’s being mimicked will cycle between 5 different items, even after Modeling Clay changes.
  • Isaac's Tomb Isaac's Tomb / Voodoo Head Voodoo Head: If Isaac can enter a trapdoor to the next floor while it’s being mimicked, they will have their normal effects.
  • Little Baggy Little Baggy / Polydactyly Polydactyly / Starter Deck Starter Deck: Allows Isaac to hold two cards and/or pills if he picks them up while Modeling Clay mimics the item, and he will continue to hold both even after Modeling Clay changes. If Isaac tries to pick up another card/pill after Modeling Clay changes, the inactive card/pill he was holding will be destroyed and he will only be able to hold one card/pill again.
    • If Isaac goes to a new room while Modeling Clay mimics Starter Deck/Little Baggy, cards/pills in the new room will be converted appropriately.
  • Member Card Member Card: The special trapdoor will not spawn.
  • Missing No. Missing No.: Does not reroll items, unless carried to another floor.
  • Sacred Orb Sacred Orb: Temporary items are affected by Sacred Orb.
  • Sanguine Bond Sanguine Bond: The unique spikes will not spawn.
  • Schoolbag Schoolbag: If Isaac picks up another active item while Modeling Clay mimics the item, the other active item is dropped after Modeling Clay changes.


  • Golden Trinket Golden Trinket / Mom's Box Mom's Box: Increases the chance of triggering to 100%.
  • Rock Bottom Rock Bottom: Permanently increases Isaac's stats when it transforms into an item that surpasses Isaac's current stats.
    • This allows the player to enter and exit a room any number of times in order to get as many stats as possible.


(This section needs revision after patch 1.7.5 which locks Modeling Clay to one item per room.)

Because Modeling Clay can constantly cycle between items by constantly exiting and re-entering rooms, many items’ effects can be forced with enough patience to get maximum value out of the trinket. Aside from the interactions listed above, the following items/effects can be forced in order to gain value from the trinket in the following ways:

  • Explosive shots: Allows Isaac to destroy rocks and open Secret Room Secret Room doors without spending resources.
  • Damage-triggered items: To gain extra value from using Machines/Beggar.png Beggars that take health or Sacrifice Room Sacrifice Rooms. Note that stats given by on-hit items will not persist outside the rooms they were used in.
    • Hallowed Ground Hallowed Ground can be used first to spawn a white poop next to a Machine/Beggar that takes health to give Isaac the chance to resist damage taken from using them.
  • The Battery The Battery: Allows Isaac's active item to be overcharged; overcharging will persist after Modeling Clay changes.
  • Cancer Cancer / The Wafer The Wafer: Reduces the damage taken from Sacrifice Rooms to half a heart, allowing Isaac to use them more.
  • Echo Chamber Echo Chamber: Cards and runes’ effects will be stacked if used while it mimics the item. The game will remember what cards and runes were used if it turns into Echo Chamber in the future, even on later floors.
  • Lucky Foot Lucky Foot / PHD PHD / Virgo Virgo: Bad pills will be their good counterparts while mimicking these items, making them much safer to use.
  • Marbles Marbles: Allows trinkets to be smelted if Isaac can deal damage to himself while it mimics the item.
  • Pyromaniac Pyromaniac: Lets Isaac heal off explosions in the current room. Can be used to greater effect in rooms with TNT TNT or Bomb Bum.png Bomb Bums.
  • Restock Restock: Items will restock themselves as normal.
  • Scapular Scapular: To gain a Soul Heart Soul Heart if at low health. This will not work if the damage source is considered "health donation", such as from a Blood Donation Machine.png Blood Donation Machine, Devil Beggar.png Devil Beggar, Confessional.png Confessional, or Hell Game.png Hell Game, but it will work for Curse Room Curse Rooms and Sacrifice Room Sacrifice Rooms.
  • Sharp Plug Sharp Plug: Isaac’s active item can be instantly recharged at the cost of red hearts.
  • Steam Sale Steam Sale: Shop Shop items and pickups will be discounted.
  • Tarot Cloth Tarot Cloth: Cards will have their effects boosted.

In-game footage[]


  • The trinket's icon appears to be a clay model of Meat Boy from Super Meat Boy, another game by Edmund McMillen.
  • The item is a direct reference to the item of the same name in The Binding of Isaac: Four Souls, which turns into another available item when used.
  • In addition, the item is possibly a reference to the Self-forming Clay item from the rogue-like deckbuilder Slay the Spire


Bug Bug! Walking between rooms back and forward with Modeling Clay may cause the game to crash at random.
Bug Bug! Normally, Modeling Clay's appearance changes to reflect what item it's imitating. This is not the case if the trinket is absorbed, e.g. through Smelter Smelter. It will appear in the Found HUD where passive items appear, like other absorbed trinkets, but will never change its appearance.