Tears now have a 10% / 20% chance to apply a shrinking effect, causing enemies to shrink in size and also run away from Isaac.
Shrunk enemies can be crushed and killed by walking over them.
Enemies that spawn from the death of a shrunken enemy will also be shrunken upon spawning. Enemies that release projectiles, explosions or other effects such as Soul Suckers no longer perform their effect when killed while shrunken.
The shrinking effect lasts 5 seconds and enemies will flash white when the effect is about to end.
This item belongs to the Fun Guy set. Collecting three items from this set will transform Isaac into a walking mushroom.
Notes
The shrinking effect does not affect bosses or mini-bosses.
Champions and enemies that explode upon death will damage Isaac if crushed.
Shrinking the heart of a Mask + Heart will cause its corresponding Mask to shrink as well. The Mask can be crushed and killed separately.
The chance to fire a shrinking tear does not scale with Luck.
Synergies
Compound Fracture / Cricket's Body / The Parasite: Split tears will retain shrinking effect if main tear had shrinking effect. With Compound Fracture and The Parasite, tears with a shrinking effect look like normal tears.
Finger!: Finger can also apply the shrinking effect.
Lachryphagy: Will occasionally fire tears with shrinking effect. All burst tears have a chance to apply the shrinking effect.
10% / 
20% chance to apply a shrinking effect, causing enemies to shrink in size and also run away from Isaac.
Enemies that spawn from the death of a shrunken enemy will also be shrunken upon spawning. 
Soul Suckers no longer perform their effect when killed while shrunken.
Fun Guy set. Collecting three items from this set will transform Isaac into a walking mushroom.
Mask + Heart will cause its corresponding Mask to shrink as well. The Mask can be crushed and killed separately.
Compound Fracture / 
Cricket's Body / 
The Parasite: Split tears will retain shrinking effect if main tear had shrinking effect. With Compound Fracture and The Parasite, tears with a shrinking effect look like normal tears.
Finger!: Finger can also apply the shrinking effect.
Lachryphagy: Will occasionally fire tears with shrinking effect. All burst tears have a chance to apply the shrinking effect.
The Ludovico Technique: Tear flickers blue, capable of shrinking enemies when it does.
Technology Zero: Electricity connected to tears with shrinking effect has a chance to shrink enemies.
Blood Puppy: If an angry Blood Puppy is shot with a God's Flesh tear, Isaac can instantly change it back to a tamed Blood Puppy by touching it.
Haemolacria: Only main tear has a chance to apply a shrinking effect.
Brimstone / 
Azazel: Brimstone laser becomes blue.
Mushrooms 
The Binding of Isaac: Rebirth
