Buddy in a Box
Grants a familiar with a random tear effect. The familiar is randomized at the start of each floor.
Spawns a familiar that follows Isaac around and fires spectral tears.
Grants piercing and spectral tears. Increases tear size (without increasing damage) while greatly reducing range and shot speed.
Spawns a friendly familiar leech on the ground that hunts down enemies and heals you for half a heart each time it eats one.
Allows Isaac to carry two cards or pills (or a combination of both) at the same time.
All sources of damage that would cause more than one half heart of damage are reduced to one half heart instead.
Key Piece 2
Combined with Key Piece 1, unlocks the golden gate in the starting room of The Chest and Dark Room to fight Mega Satan.
Increases Damage by 1.5, reduces Tears by 0.3 and increases tear size. Grants piercing tears. Tears are replaced by Death's scythes, which is a cosmetic effect only.
Cube of Meat
Orbiting familiar that blocks enemy shots and deals damage to enemies. If collected while already having one, makes the familiar evolve. Only drops from Horsemen. Similar to Ball of Bandages.
Grants Isaac 1 Black Heart and 3 bombs. Can also give troll bombs.
Grants spectral tears that travel through obstacles (but not enemies) instead of breaking on impact with them.
Isaac's head is removed from his body and floats around him. Increases Damage by 1 and grants -1 Tear Delay.
Gives 6 coins, 6 bombs, and 6 keys and balances out all attributes.
Increases damage and increases the chance for a Devil or Angel Room to appear.
Ball of Tar
Adds a chance to shoot slowing tears and the character leaves a trail of slowing creep behind as he moves, impeding enemies' speed.
Spawns a fly familiar that orbits around a random enemy and deals 5 damage per tick to enemies it comes in contact with.
If the character has half a red heart or no red hearts after taking damage, it triggers the Book Of Shadows effect, creating a shield that nullifies all types of damage for 5 seconds. Also allows entrance into The Chest.