Poops

Can be destroyed by tears, explosions, stomping effects (such as Thunder Thighs), and certain effects that grant invulnerability (such as The Gamekid and My Little Unicorn).
Has a 10% chance to drop a pickup when destroyed. Of those, 3/4 are coins (7.5% of all poops) and 1/4 are hearts (2.5% of all poops).
0.5% or 1/200 poops drop Petrified Poop (if not yet discovered/held).
Can fill in a gap to create a bridge when pushed in the right direction by an explosion, or by walking into them with Leo/Thunder Thighs.
If a Fly stays around Poop for long enough, it will morph into a Pooter.
Destroying 100 poops unlocks the Butter Bean.

Corny Poop

Has the same chance to drop coins, hearts, and Petrified Poop when destroyed as regular poop.
Has an Eternal Fly orbiting it that will become an Attack Fly upon destruction of the poop. If Isaac leaves the room without destroying the poop, the orbit of the Eternal Fly will be smaller when he returns.
Corny poops thrown by Tainted ??? or IBS spawn up to 3 Blue Flies.

Deals a half-heart of contact damage.
- Leo/Thunder Thighs allows Isaac to walk over and destroy red poop without taking damage. Isaac will still take damage if he is standing on it when it reforms, however.
Deals 16 contact damage to enemies.
Drops nothing when destroyed.
Reforms 3 seconds after being destroyed.
Normally produced by Carrion Queen and red champion Dingle, but can also be found in specific room configurations in various rooms.
- In the Scarred Womb, rocks in any room have a chance to be replaced by red poop.
- Carrion Queen and red champion Dingle can produce a Red Poop on the Boss Item tile. When the item spawns, the Red Poop will be camouflaged behind the item.
In some rooms that need to be cleared by pressing silver buttons, red poop will turn into regular poop once all the buttons are pressed.

Harder to destroy than the normal poop.
Drops 5-9 coins or the Counterfeit Penny trinket when destroyed.
If a Fly comes in contact with a Golden Poop, it will turn into a Pooter.
When fighting Ultra Greed, all poop spawned in the boss room will turn into Golden Poop.
When fighting Ultra Greed, all poop spawned in the boss room will turn into Golden Poop; however, it will not have any of the money-giving effects.

Causes a rainbow to appear on the screen when destroyed; pauses the game for a second while playing a jingle.
Restores all of Isaac's heart containers when destroyed, regardless of what destroyed it. Also affects all Co-op players.
Rainbow Poop provides no benefit for characters without red heart containers (such as ???).
If a Fly comes in contact with a Rainbow Poop, it will turn into a Pooter.

Darkens the current room as if Glaucoma was active for a few seconds when destroyed. This effect gets overlapped by Number Two and vice-versa.
Deals 10 damage and applies the 'Confusion' status effect to all enemies in the room when destroyed.
Does not normally spawn any pickups when destroyed, even with Petrified Poop (but see the point below).
Has a small chance of spawning a Black Heart upon being destroyed if Isaac holds Meconium.

Has the same chance to drop coins, hearts, and Petrified Poop when destroyed as regular poop.
Will be spawned if Isaac is injured while using Hallowed Ground.
- Can also be thrown by Tainted ??? or with IBS.
White poop is surrounded by an aura. While standing within the aura, tear delay is halved, it has a high chance to block damage like the Cone Head item, damage is increased by 25%, and tears become homing.
The aura disappears if the poop is destroyed.
Harder to destroy than normal poop, though not as durable as golden poop.

Occurs only in 4 rare room layouts in Dross.
Requires a large amount of tears to destroy.
Drops different pickups when hit.
- Can drop coins, Red Hearts, Soul Hearts, Eternal Hearts, and the Petrified Poop trinket.
- Drops a lot more pickups when holding the Petrified Poop.
Using an Infested! pill on it will spawn 4 blue spiders (8 with a Horse Pill) and decrease the poop's stage by 1.
Unlike with other poops, breaking this poop variant whilst having the Oh Crap transformation won't restore any health.

Acts like a normal Brown Poop, but spawns Dip Familiars when damaged or destroyed, similar to Dirty Mind.
Unlocked by: Defeat Mega Satan as Tainted ???

Isaac's creator, Edmund McMillen, has mentioned having IBS in real life — as well as Isaac having it in-game. This could explain the large variety of poops throughout the game.
Edmund McMillen confirmed that red poop causes damage "because it is made out of AIDS".

Bug!	If a poop is destroyed by an item pedestal spawning, collecting the item then leaving and re-entering the room will cause the poop to reappear, dropping its reward twice. This is especially remarkable for golden poops.

Bug!	If a poop is pushed by an explosion to fill in a gap, a bridge will be created even if the poop survives the explosion. This way, it is possible to fill more than one gap with a durable poop such as golden poop.