Some ideas:

Saturn - Bombs circle around you. Bombs spawned this way do not harm you, and only explode upon hitting an enemy when it is able to be damaged
Ocular Rift - When a bomb explodes, it has a chance to create a larger Rift
Rocket in a Jar - Bombs will fly as if they are tears.
Decap Attack - Upon your head landing, it will explode.
Immaculate Heart - Bombs have a chance to not explode, and will instead circle around you.

Modded Ideas:

Perseverance (Revelations) - Bombs will only damage enemies targeted by Perseverance
Burning Bush (Revelations) - Spawn mini flaming bombs instead of a single flaming bomb
Pilgrim's Reward (Revelations) - Bombs fired after reaching the first Sigil will mark the next Sigil
Pride's Posturing (Revelations) - The first bomb tossed fires Pride Lasers
Lil' Michel (Revelations) - Lil' Michel tosses bombs launched by you. Counts as 5 tears to Lil' Michel's requirements
Mint Gum (Revelations) - Bombs roll much slower. With Rocket In a Jar, the same will apply with rocket speed
Ophanim (Revelations) - Ophanim will fire mini bombs instead of tears. Ophanim won't detach if you take damage from your own bombs
The Monolith (Revelations) - tossing bombs instead of tears fires Mega Blast lasers
Envy's Enmity (Revelations) - Firing bombs through Envy heads instead refreshes explosion timer
Ice Tray (Revelations) - Freezes your bombs, allowing you to knock them around
Crackling Slag (Quarry Collection) - Fires Mega Bombs. Pick up at your own risk.
Ancestral Assistance (Toybox Collection) - Has a chance to fire a arrow of bombs
Glad Bombs (Tainted Treasures) - Bombs will fire mini-bombs instead of tears
Consecration (Tainted Treasures) - Bombs will unleash 3 rings of fire around them
The Bottle (Tainted Treasures) - Behaves the same as The Knife.
Polycoria (Tainted Treasures) - Fires a cluster of mini-bombs
Colored Contacts (Tainted Treasures) - Bombs explode with more range when enemy tears pass through them
Lil' Slugger (Tainted Treasures) - Bombs unleash SAWBLADES in the direction you've originally fired the bomb containing the SAWBLADES
Evangelism (Tainted Treasures) - Bombs emit a static aura, that when an enemy is within for a duration, will cause the bomb to explode.

Vanilla Ideas:
Spirit Sword:Bombs make a sword spin when they explode

Modded Ideas:
Slippy Tooth(Sewage Collection):Bombs have a chance to inflict enemies with 'slippy' when they survive the explosion! Bombs also a puddle of brown creep upon exploding!
Plastic Bag(Sewage Collection):Bombs make an explosive gas cloud when they explode!
Hypno Ring(Fiend Folio):Bombs have a chance to inflict 'drowsy' on enemies that survive the explosion
Duke of Eyes(Duke Mod):Bombs have a chance to spawn random heart flies or spiders when they damage enemies!
Arrowhead(Tainted Treasures):Bombs can go through the player and once done it,they gain a speed boost and penetrate enemies!

Epic Fetus: When bombs explode, they shoot out 4 Epic Fetus reticles in the cardinal directions (This kinda acts as a reverse of Epic Fetus + Scatter Bombs/Split Tears)
Neptunus: Bombs launch a Monstro's Lung-style volley of tears in the direction you fired them when they explode.
Pop!: Bombs have a much longer delay before exploding, and bounce off of eachother more aggressively. They explode instantly when hitting an enemy, or when hitting walls (unless you also have Rubber Cement.)
Lead Pencil: Shoot a volley of tiny bombs every 15 shots.
Fast Bombs: Massive tears up.
Eye of Greed: Every 20 shots, lose 1 coin to shoot a golden bomb that explodes into coin tears that turn enemies to gold.
Compound Fracture: Occasionally create Bone Spurs fragments when bombs explode.
Backstabber: Bombs deal contact damage and inflict bleeding when hitting the back of an enemy.

My ideas:
Midas' Touch: Turn bomb into gold bomb that have small chance to turn enemies into gold on contact.
Flat Stone: Bomb can now jump through 1 hole/rock.
Uranus: Bombs will freeze enemies.
Mars: On dash place 1-2 bomb on way.
Glass Cannon: On use shoot Giga bomb.
Tooth and Nail: Bomb have contact damage.
Bird's Eye/Ghost Pepper: Bombs have small chance to shoot fires in 8 directions (like Sad Bombs but fires instead tears)
Tear Detonator: On use split bombs on 3 bombs that have less damage.
Chocolate Milk: Full charged bomb deal more damage.
Black Powder: Bombs on explode makes small pentagram.
Anemic: If player gets hurt bombs act like Blood Bombs.
Best Friend: Bombs have small chance to attrack enemies.
A Pony: Acts like Mars but more bombs.
Gnawed Leaf: Bombs have small chance to turn enemies into rock statue that works like Reversed Chariot.
Lemon Mishap: Bombs now makes small yellow creep.
Free Lemonade: Bombs have chance to make big yellow creep.
Void: Bombs now suck enemies.
Undefined: Makes random bombs (from mini bombs with random effect to Giga bomb)
The Bible: Creates holy light on bomb explosion.

lachryphagy: bombs are slightly magnetic, and absorb into eachother and become bigger, leading to more damage and a bigger explosion radius
they can also absorb normal bombs which adds more damage and radius compared to normal bombs

Ngl I made an entire document before this mod was made for potential Dr. Fetus synergies with as many (base-game) passive items as I could think of

You'll need them more than me, so here they are:

https://docs.google.com/document/d/1D-rOeMgqK_ZyEP97mhWgXN4jnV0BhKSt_CQGfAOwnXU/edit

Originally posted by MinervoIonni:

Ngl I made an entire document before this mod was made for potential Dr. Fetus synergies with as many (base-game) passive items as I could think of

You'll need them more than me, so here they are:

https://docs.google.com/document/d/1D-rOeMgqK_ZyEP97mhWgXN4jnV0BhKSt_CQGfAOwnXU/edit

Wtf

Originally posted by JamesB456:

Originally posted by MinervoIonni:

Ngl I made an entire document before this mod was made for potential Dr. Fetus synergies with as many (base-game) passive items as I could think of

You'll need them more than me, so here they are:

https://docs.google.com/document/d/1D-rOeMgqK_ZyEP97mhWgXN4jnV0BhKSt_CQGfAOwnXU/edit

Wtf

What

Originally posted by MinervoIonni:

Originally posted by JamesB456:

Wtf

What

How do you have this many ideas?

How do you have this many ideas? [/quote]
I think about Isaac too much lmao

I broke it

Originally posted by MinervoIonni:

I broke it

Lol

Originally posted by JamesB456:

Lol

Btw, if you want I could try doing the same for Spirit Sword too

Originally posted by MinervoIonni:

Originally posted by JamesB456:

Lol

Btw, if you want I could try doing the same for Spirit Sword too

Sure. The more ideas, the better.

id like a sad bombs synergy
like when you shoot out a bomb it shoots out tears when it explodes
(or maybe do this for epic fetus idrk)