Dead Onion

Dead Onion is a passive item.

Effects

Grants piercing and spectral tears.
Increases tear size (without increasing damage).
+0.25 Range.
-0.4 Shot Speed.
-0.5 Shot Height.

Synergies

Euthanasia: When needles are fired, they retain spectral and piercing effects, although they disappear at short range.
Haemolacria: Tears are fired much more slowly, making it easier to aim at enemies. Tears are also much bigger making it easier for them to hit enemies.
Incubus: Does not affect shot speed or tear size but still gives the piercing effect.
Ipecac: Slows your tears, making it easier to aim at enemies.
Lachryphagy: Fired tears and burst tears will retain spectral and piercing effects. They are also bigger, making them easier to burst.
Lost Contact: The tears can pass through multiple enemy projectiles. This means that one tear can both hurt an enemy and block its projectiles.
The Parasite: Tears continue to pass through enemies and create additional tears on contact.
Tech X: Lower shot speed allows laser rings to hit enemies more.
Tiny Planet: Tears become bigger, orbit more slowly, and orbit closer to Isaac making it easier to hit enemies.

Interactions

Azazel: No effect as Azazel's Brimstone attack is already piercing and spectral; effective range remains the same.
Compound Fracture: Bone tears retain all effects and will only burst into bone shards when passing through enemies or obstacles.
Cricket's Body: Not recommended without pre-existing range boosts, as it significantly decreases effective range.
Dr. Fetus: Not recommended. Bombs are slow to fire and will pass through enemies, making it far more difficult to hit them with explosions.
Epic Fetus: Overrides Dead Onion, although stat effects apply.
The Ludovico Technique: Not recommended. Tear moves very slowly making it hard to kill mobile enemies.
A Lump of Coal: Tears will grow and increase in damage as they travel; however, since Dead Onion decreases shot speed, they don't get much benefit before they disappear.
Mom's Knife: Overrides Dead Onion.
Monstro's Lung: Fires a barrage of large tears that disappear at close range. Spectral and piercing effect make it very effective at close range.
My Reflection: Not recommended. Tears will travel a very short distance before they return to Isaac and eventually disappear.
Proptosis: Not recommended. While tears do massive damage at short range, it makes it a lot easier to be damaged by explosive enemies or enemies that do contact damage.
Rubber Cement: Edges of tears retain both piercing and spectral effects, however the center of the tear will lose them and bounce.
Trisagion: Not recommended. Beams are slow to fire and disappear quickly.
Sulfuric Acid: Not recommended. Acid Tears no longer impact objects and can no longer open secret rooms.