Upon use, creates an explosion on Isaac's position.
The explosion damages Isaac for half a heart of health (or a full heart in Chapter 4 onward).
The explosion deals 40 damage.
The size and damage of the Kamikaze! explosion is identical to that of a Mr. Mega bomb, dealing 185 damage in a wide radius.
Notes
The explosion will damage Soul Hearts before Red Hearts, unlike most other self-damaging active items.
Despite the explosion usually damaging Isaac, Kamikaze! is not considered a self-damaging item because it is not the item's use which causes the damage, but rather the resulting explosion. This has a few consequences:
Kamikaze! does not bypass invincibility, which means items such as Holy Mantle or Tooth and Nail work normally.
Kamikaze!'s cool down length is as long as the invincibility frames Isaac normally gets from being hit. This means that Isaac cannot activate Kamikaze!, and then activate Kamikaze! again before the invincibility frames end.
Synergizes with many bomb-enhancing items such as Bob's Curse, with exceptions listed in Interactions.
Book of Virtues: Spawns wisps in the middle ring that looks like small sticks of dynamite. The wisps fire explosive projectiles and explode when destroyed, dealing 30 damage to enemies that are close to it. This explosion is small enough to not always hit Isaac, although it will hurt him should he get caught in it. All explosions the wisps make are unaffected by BFFS! and bomb synergies.
Dark Arts: Kamikaze can be used for free while Dark Arts is active.
Gnawed Leaf: Activating Kamikaze will cancel out of the statue state, but Isaac will not be damaged by the resulting explosion.
Host Hat: Allows unlimited uses without consequences.
Mars: Isaac is invincible during the dash, allowing for unlimited uses with careful timing.
Nancy Bombs: Gains the effect of a random bomb synergy each time it is used.
Pyromaniac: Allows unlimited uses and heals without consequences.
Each use will heal Isaac for one full / half a red heart.
Sigil of Baphomet: Isaac can chain-kill enemies without taking explosion damage while the shield is active.
Schoolbag: The cool down before the player can use Kamikaze! again is eliminated when switching items. Depending on how fast the player can push the buttons, Kamikaze! can be used multiple times during Isaac's invincibility frames.
Tainted Forgotten: Explodes on Tainted Forgotten’s body, meaning that it is safe to use infinitely, so long as Tainted Soul is not within the blast radius.
Blind Rage: With longer invincibility, Isaac can use Kamikaze! a second time without taking damage.
Panic Button: Isaac will use Kamikaze before taking damage, similarly to Swallowed M80, with the exception that, if Kamikaze triggers on red health, it will not affect devil/angel deal chances, effectively preserving it.
Jacob and Esau: Jacob will always take damage if he activates the item. Esau will take damage when he uses it, but only if Jacob is not inside the blast radius. If Jacob is within the blast radius, he will take damage despite Esau holding the item, and Esau will not take damage.
Soul of the Forgotten/Strawman: The Forgotten or Keeper will take damage if they are caught within the blast radius.
Sigil of Baphomet: Defeating an enemy gives Isaac a 1-second window to use Kamikaze! without taking damage.
Defeating enemies with Kamikaze! further extends the shield's duration, allowing for more free uses of it.
Swallowed M80:The damage received from Kamikaze itself can trigger it, dealing 370 damage total in the form of 2 rapid explosions on top of Isaac.
This only works if Isaac takes damage from the explosion.
3DS The icon of Kamikaze! as seen on the lower 3DS screen.
Trivia
The term kamikaze comes from the Japanese language (神風, divine wind), and refers to Japanese pilots that would blow up their aircraft and themselves to damage enemy targets during World War II.
Soul Hearts before 
Red Hearts, unlike most other self-damaging active items.
Holy Mantle or 
Tooth and Nail work normally.
Devil Room/
Angel Room chance is lowered if red heart damage is taken.
Bob's Curse, with exceptions listed in Interactions.
The Book of Belial + 
Birthright as 
Judas / 
Dark Judas: Invokes the effect of 
The Necronomicon effect along with the original effect.
Book of Virtues: Spawns wisps in the middle ring that looks like small sticks of dynamite. The wisps fire explosive projectiles and explode when destroyed, dealing 30 damage to enemies that are close to it. This explosion is small enough to not always hit Isaac, although it will hurt him should he get caught in it. All explosions the wisps make are unaffected by 
BFFS! and bomb synergies.
Dark Arts: Kamikaze can be used for free while Dark Arts is active.
Glitter Bombs: Has a chance to drop a pickup or trinket each time it is used.
Gnawed Leaf: Activating Kamikaze will cancel out of the statue state, but Isaac will not be damaged by the resulting explosion.
Host Hat: Allows unlimited uses without consequences.
Mars: Isaac is invincible during the dash, allowing for unlimited uses with careful timing.
Nancy Bombs: Gains the effect of a random bomb synergy each time it is used.
Pyromaniac: Allows unlimited uses and heals without consequences.
Sigil of Baphomet: Isaac can chain-kill enemies without taking explosion damage while the shield is active.
Schoolbag: The cool down before the player can use Kamikaze! again is eliminated when switching items. Depending on how fast the player can push the buttons, Kamikaze! can be used multiple times during Isaac's invincibility frames.
Tainted Forgotten: Explodes on Tainted Forgotten’s body, meaning that it is safe to use infinitely, so long as Tainted Soul is not within the blast radius.
Blind Rage: With longer invincibility, Isaac can use Kamikaze! a second time without taking damage.
Panic Button: Isaac will use Kamikaze before taking damage, similarly to 
Swallowed M80, with the exception that, if Kamikaze triggers on red health, it will not affect devil/angel deal chances, effectively preserving it.
Jacob and Esau: Jacob will always take damage if he activates the item. Esau will take damage when he uses it, but only if Jacob is not inside the blast radius. If Jacob is within the blast radius, he will take damage despite Esau holding the item, and Esau will not take damage.
Soul of the Forgotten/
Strawman: The Forgotten or Keeper will take damage if they are caught within the blast radius.
Bombs 
The Binding of Isaac: Rebirth
