Hidden Attributes

Attributes

Health

Damage

Tears

Range

Shot Speed

Speed

Luck

Hidden Attributes

Tear Height

Tear Height is a hidden attribute that determines how far above the ground tears travel. A greater tear height effectively increases range, and a high enough tear height (around 3) can allow tears to fly over obstacles without spectral tears.

Items that affect shot height

Passive Items

Name	ID	Icon	Quote	Description
Blood Clot	254		DMG + range up	Increases damage by 1 and range by 5 for tears fired from the left eye.
Compound Fracture	453		Bone tears!	Increases range. Tears turn into bones, which shatter into 1-3 bone shards upon hitting an enemy or obstacle.
Continuum	369		Transcendent tears	+2.25 Range Up. +1.5 Tear Height. Isaac's tears travel through walls and appear out of the opposite wall. Isaac's tears also travel over rocks and objects.
Dark Prince's Crown	442		Loss is power	Increases range, tears, and shot speed when at exactly one red heart.
Dead Onion	336		Toxic aura tears	Grants piercing and spectral tears. Increases tear size (without increasing damage) while greatly reducing range and shot speed.
Godhead	331		God tears	Increases damage and range while reducing tears and shot speed. Grants homing tears and tears gain a damaging halo.
The Halo	101		All stats up	Grants one Heart Container, +0.3 Damage, +0.2 Tears, +0.25 Range, +0.3 Speed, and +0.5 Tear Height.
Ipecac	149		Explosive shots	Replaces tears with explosive and poisoning projectiles fired in an arc from the mouth.
Jesus Juice	197		Damage + range up	Increases Damage and Range.
Kidney Stone	440		Matt's kidney stone	Randomly while firing tears, Isaac will stop firing and turn red, where he will charge and release a lot of 'tears' in one go. In the burst of tears is a kidney stone which deals a lot of damage.
Magic Mushroom	12		All Stats Up!	Increases most stats, enlarges Isaac, grants a heart container and restores all health.
Marked	394		Directed tears	Isaac will now fire tears automatically directed at a red target on the ground which is controlled by the player. This allows for a full 360 degree tear firing radius. Can be overridden by other tear modifiers such as Mom's Knife or Brimstone.
Mini Mush	71		Speed + range up	Increases Speed and Shot Height and decreases Isaac's size, but lowers Range.
Mom's Contacts	110		Freeze effect	Adds a chance to shoot petrifying tears, which stop enemies in place and prevent them from moving or attacking. Range up.
Mom's Heels	30		Range up	Increases range.
Mom's Lipstick	31		Range up	Increases range and shot height.
Mom's Pearls	355		Range + luck up	+1.25 Range Up. +0.5 Tear Height. +1 Luck Up.
Mom's Underwear	29		Range up	Increases range.
Mr. Dolly	370		Range + tears up	Tears and Range up. Spawns 3 random types of hearts on the floor when picked up.
My Reflection	5		Boomerang tears	Gives Isaac's tears a boomerang effect, and increases range and shot speed.
Number One	6		Tears up	+1.5 tears, -17.62 range
Odd Mushroom	121		DMG up	Grants an empty heart container. Increases damage, range and shot height while reducing speed.
Purity	407		Aura stat boost	This item will boost one of Isaac's stats depending on the color of the aura around him. The aura will disappear upon taking damage and will reappear with a random color upon entering a new room. A red aura boosts damage, a blue aura boosts rate of fire, a yellow aura boosts speed, and an orange aura boosts range.
Roid Rage	14		Speed and range up	Increases speed by 0.6, range by 5.25, and tear height by 0.5.
Sacred Heart	182		Homing shots + DMG up	Increases damage and range while reducing shot speed and grants homing tears. Grants a Heart Container and replenishes all Red Hearts.
Safety Pin	339		Evil + range + shot speed up	Increases range and shot speed, while adding 1 Black Heart.
Synthoil	345		DMG up + range	Increases damage by 1, range by 5.25, and tear height by 0.5.
Tiny Planet	233		Orbiting tears + range up	Range up and makes shot tears revolve around Isaac until they drop.
Tractor Beam	397		Control your tears	Isaac emits a beam from his face. Isaac's tears travel in the path of the beam.

Trinkets

Name	ID	Icon	Quote	Description
Lazy Worm	66		Pft	Tear shot speed is greatly reduced.
Ouroboros Worm	96		Foop foop!	Tears travel in a large spiral pattern and become spectral.
Tape Worm	65		Floooooooooop!	Doubles Isaac's range and halves his tear height.

Other

• In co-op, Long Baby will occasionally briefly increase range, shot speed, and tear height. Dark Baby will occasionally briefly increase all stats, including tear height.
• Azazel starts with -1 tear height, though the stat does not affect his short-range Brimstone.

Knockback

Knockback is a mechanic that determines how far an entity is pushed back by a certain force.

There are two kinds of knockback: directional and circular.

Directional Knockback

This knockback comes from Tears, most notably Isaac's. The knockback force is determined by the speed and direction of the tear, which itself is determined by Isaac's movement and stats, for example Ring Worm does not increase knockback stat but does affect knockback as the tear's speed hits extremes of very fast and very slow, hitting enemies with the fastest moment of its arc applies significant knockback. (Needs research and confirmation)

Directional knockback affects most enemies, including bosses (except for stationary ones like Pin or Round Worm). Items (both Trinkets and Pickups) cannot be moved by tears, except for bombs placed by Isaac.

Items that affect directional knockback

Passive Items

Name	ID	Icon	Quote	Description
8 Inch Nails	359		Stick it to 'em!	+1.5 Damage Up. Replaces Isaac's tears with nails, which have increased knockback.
Pisces	309		Tears up + knock-back shots	-1 Tear Delay, adds knock-back shots and increases tear size.

Trinkets

Name	ID	Icon	Quote	Description
Blister	77		Bounce back!	Increases knockback of tears.
Flat Worm	12		Blub blub!	Isaac's tears take on an oblong appearance. They also push enemies back.

Notes

• Piercing shots from items like Sagittarius or Cupid's Arrow will remove the natural knockback from tears, but direct boosts still apply. Flat WormIsaac's tears take on an oblong appearance. They also push enemies back. increases only natural knockback and is thus nullified.
• Knockback from tears provides minor crowd control for homing enemies like flies or Gapers, increasing the time it takes them to reach Isaac.
• Be wary of the natural knockback from tears when trying to dodge charging enemies (like the smaller twin of Gemini, Gurglings, and Leeches): The tears can push them off-track and towards the direction you are planning to escape to.

Circular Knockback

This knockback is a little shockwave that's emitted at a certain radius in all directions, most prominently from explosives, like Bombs.
Certain farts also create a (non-harmful) knockback. Some enemies, like the Fatty, can fart, and Isaac can also do so with the Butter Bean.

Pickups (including Chests) are affected by circular knockback; items, however, are not.

Items that cause circular knockback

Activated Items

Name	ID	Icon	Quote	Description
Butter Bean	294		Reusable knock-back	Isaac farts and pushes back nearby enemies.
The Poop	36		Plop!	Spawns a pile of poop where the character is standing and knocks nearby monsters back. May yield pickups like regular poop.

Passive Items

Name	ID	Icon	Quote	Description
Farting Baby	404		It farts!	A familiar that follows Isaac and blocks tears. If a tear hits Farting Baby, there is a high chance for it to fart, which will either knock back, poison, or charm all nearby enemies.

Trinkets

Name	ID	Icon	Quote	Description
Butt Penny	24		Wealth of gas	Isaac will fart when he picks up a coin.
Mysterious Candy	25		Uh-oh!	Isaac farts or poops at random intervals. Getting hit can also trigger the effect.

Notes

• There is also a mechanic that acts as an opposite of sorts to circular knockback: a gravitational pull that is emitted from Gaping Maws, Mega Fatty (while charging up its "Vomit Storm" attack), purple Champion monsters, magnetic tears, and suction pitfalls.