Azazel suffers from the shortest range of all characters; this is balanced with flight, additional power per hit via his Brimstone-like attack, and significant damage to all enemies in the room upon the loss of a Black Heart, killing most lesser enemies.
Due to his flight, Azazel takes damage only when leaving a Curse Room, not when entering, effectively letting him use these rooms at half-price. Additionally, he can use the Fool card he starts with to avoid the cost for one room entirely.
It is possible to slightly increase attack range by taking range-increasing items.
Despite his lack of Red Heart containers, unlike ???, Azazel can gain Red Heart containers. Thus, health-increasing items are useful.
With enough range, acquiring homing tears will make Azazel's Brimstone home in on enemies.
20/20 doubles lasers without increasing tear delay.
Abaddon aside from the lack of Angel Rooms, it provides no downside, given Azazel still has no Red Heart containers. As it costs 3 Soul Hearts, it will add 3 Black Hearts to his health bar, increase damage and speed, and give his Brimstone laser a fear effect.
This has been significantly nerfed in The Binding of Isaac: Repentance, as the amount of black hearts given by Abaddon is now based on the the amount of red hearts it took.
The Ludovico Technique gives a Brimstone ring, whether Azazel has the short or long-ranged version of it, giving him the ability to damage many enemies at a time due to its size and negates Azazel's short-range, but halves Azazel's damage.
Mom's Eye allows Azazel to shoot two beams, one of which is shot behind him.
Monstro's Lung gives several additional Brimstone beams around Azazel.
My Reflection greatly increases the range of Azazel's brimstone.
Greatly increases the Brimstone laser's range and makes the laser curve as Azazel moves around the room.
Greatly increases the Brimstone laser's range and makes the laser double back on itself to land behind Azazel.
Number One slightly decreases Azazel's range but significantly decreases the charge time of Azazel's Brimstone. It also turns Azazel's laser yellow.
Proptosis doubles the Brimstone laser's damage without any downsides.
The beam will decrease in damage the further it travels, but Proptosis still greatly increases damage at close range.
Rubber Cement allows Azazel's laser to bounce off of walls. Unlike Azazel's normal mini-Brimstone, beams that bounce off of walls have infinite range but deals half of the damage.
The beam will no longer turn into normal Brimstone upon bouncing off a wall. It will instead turn into his mini-Brimstone.
Sad Bombs shoots 10 short-ranged Brimstone beams around the explosion point, which deals enormous amounts of damage.
Tammy's Head shoots 10 short-ranged Brimstone beams around him, which deal enormous amounts of damage.
Tape Worm greatly increases the Brimstone laser's range.
Technology along with a physical change in the Brimstone, damage is increased.
Technology 2 provides a laser while Brimstone is charging, allowing the player to do damage while the charge occurs. However, this also decreases the damage of Azazel's Brimstone.
Tiny Planet changes the path of Azazel's Brimstone into a circle, giving it an area of effect. The range increase becomes especially powerful if you add a homing tears effect.
Cricket's Body Adds a scatter of blood tears from Azazel's Brimstone's landing point.
Marked: Azazel's Brimstone is auto-fired in the direction of a controllable target. Press Fire to start and Drop to stop.
Eye of the Occult: Azazel's Brimstone becomes a lasso, auto-fired at a controllable target. Press Fire to start and Drop to stop.
ContinuumThe range of Azazel's short Brimstone is increased and wraps around the screen, though without other significant range boosts it doesn't wrap far enough reach into the room.
Ipecac adds poison effect to the beam and fires an explosive tear, but since tear delay increases, it will make a run with Azazel much harder..
The tear delay remains unchanged, and the end of the beam is explosive. No tear is fired.
Soy Milk gives instant and everlasting brimstone. Damage is significantly decreased.
Almond Milk gives instant and everlasting brimstone. The beam will also gain random worm trinket effects, essentially acting as a mix between Soy Milk and Fruit Cake. Damage is significantly decreased.
The Wiz while useful in some situations, enemies such as The Thing or other Creeps will be dangerous.
The following items have their effect reduced or nullified with Azazel's short-ranged Brimstone.
Continuum has no effect with Azazel's short Brimstone.
The range of Azazel's short Brimstone is increased and wraps around the screen, though without other significant range boosts it doesn't wrap far enough to be reach into the room.
Kidney Stone only reduces Azazel's speed and short Brimstone's range.
Lead Pencil overridden by Azazel's short Brimstone.
Marked Brimstone's beam cannot be directed, but it does increase Brimstone's charge speed.
The beam can now be directed.
Jacob's Ladder Jacob's Ladder has no effect; sparks do not fly from Azazel's Brimstone when it connects with enemies.
Sparks appear where the brimstone ends.
The following items override Azazel's short-ranged Brimstone:
Items that break Rocks, like Leo or Thunder Thighs nullify part of the advantage Azazel gains from flight as he will no longer be able to hover over them to avoid enemy projectiles.
In the Bible, Azazel is the name given to the goat that was cast into the wild as part of Jewish atonement rituals. However, in certain traditions of Abrahamic religions, Azazel refers to the fallen angel who taught people to make weapons and jewelry and taught women the "sinful art" of painting their faces, as mentioned in the apocryphal Book of Enoch. Azazel is referenced three times in the Bible; this may be why he spawns with three Black Hearts.
Azazel's starting health is listed as "-1" on the character selection screen.
Damage
Tears
Shot Speed
Range
Speed
Luck
Pickups
0 - The Fool
Brimstone
20/20 doubles lasers without increasing tear delay.
Abaddon aside from the lack of Angel Rooms, it provides no downside, given Azazel still has no Red Heart containers. As it costs 3 Soul Hearts, it will add 3 Black Hearts to his health bar, increase damage and speed, and give his Brimstone laser a fear effect.
Chocolate Milk reduces charge time.
Circle of Protection The circle is nearly the same size as Azazel's laser, adding extra damage.
Hook Worm allows the lasers to deal more damage per tick because of the shape it takes on.
The Inner Eye/
Mutant Spider shoots multiple mini Brimstone lasers with increased tear delay.
The Ludovico Technique gives a Brimstone ring, whether Azazel has the short or long-ranged version of it, giving him the ability to damage many enemies at a time due to its size and negates Azazel's short-range, but halves Azazel's damage.
Mom's Eye allows Azazel to shoot two beams, one of which is shot behind him.
Monstro's Lung gives several additional Brimstone beams around Azazel.
My Reflection greatly increases the range of Azazel's brimstone.
Number One slightly decreases Azazel's range but significantly decreases the charge time of Azazel's Brimstone. It also turns Azazel's laser yellow.
Proptosis doubles the Brimstone laser's damage without any downsides.
Rubber Cement allows Azazel's laser to bounce off of walls. Unlike Azazel's normal mini-Brimstone, beams that bounce off of walls have infinite range but deals half of the damage.
The beam will no longer turn into normal Brimstone upon bouncing off a wall. It will instead turn into his mini-Brimstone.
Sad Bombs shoots 10 short-ranged Brimstone beams around the explosion point, which deals enormous amounts of damage.
Tammy's Head shoots 10 short-ranged Brimstone beams around him, which deal enormous amounts of damage.
Tape Worm greatly increases the Brimstone laser's range.
Technology along with a physical change in the Brimstone, damage is increased.
Technology 2 provides a laser while Brimstone is charging, allowing the player to do damage while the charge occurs. However, this also decreases the damage of Azazel's Brimstone.
Tiny Planet changes the path of Azazel's Brimstone into a circle, giving it an area of effect. The range increase becomes especially powerful if you add a homing tears effect.
Cricket's Body Adds a scatter of blood tears from Azazel's Brimstone's landing point.
Marked: Azazel's Brimstone is auto-fired in the direction of a controllable target. Press Fire to start and Drop to stop.
Eye of the Occult: Azazel's Brimstone becomes a lasso, auto-fired at a controllable target. Press Fire to start and Drop to stop.
ContinuumThe range of Azazel's short Brimstone is increased and wraps around the screen, though without other significant range boosts it doesn't wrap far enough reach into the room.
Dead Eye has no effect.
Ipecac adds poison effect to the beam and fires an explosive tear, but since tear delay increases, it will make a run with Azazel much harder..
Soy Milk gives instant and everlasting brimstone. Damage is significantly decreased.
Almond Milk gives instant and everlasting brimstone. The beam will also gain random worm trinket effects, essentially acting as a mix between Soy Milk and Fruit Cake. Damage is significantly decreased.
The Wiz while useful in some situations, enemies such as The Thing or other Creeps will be dangerous.
Compound Fracture
Cupid's Arrow
Cursed Eye
Lord of the Pit (Azazel starts with flight)
Mysterious Liquid (
Ouija Board
Pulse Worm
Spirit of the Night (Azazel starts with flight)
Strange Attractor (Until 
Anti-Gravity is picked up)
The Parasite
Kidney Stone only reduces Azazel's speed and short Brimstone's range.
Lead Pencil overridden by Azazel's short Brimstone.
Jacob's Ladder Jacob's Ladder has no effect; sparks do not fly from Azazel's Brimstone when it connects with enemies.
Ankh, 
Lazarus' Rags, and 
Judas' Shadow
Leo or 
Thunder Thighs nullify part of the advantage Azazel gains from flight as he will no longer be able to hover over them to avoid enemy projectiles.
Begotten Baby -
Defeat Mom's Heart on Hard mode as 
Lazarus
Azazel.
The Binding of Isaac: Rebirth 
Achievements
Attributes
Bosses
Cards and Runes
Challenges
Chapters
Characters
Co-op
Items
Item pools
Monsters
Objects
Pickups
Pills
Rooms
Seeds
Transformations
Trinkets
