Games like Cannon Father
Games like Cannon Father include Vampire Survivors, Megabonk, 20 Minutes Till Dawn, Death Must Die, and Enter the Gungeon. We matched them by the tags players give Cannon Father on Steam (Action, Bullet Hell, Pirates, Casual, and Early Access): closest matches first, and among equally close ones the better-known games.

Vampire Survivors
Shared: Bullet Hell · Action Roguelike · Pixel Graphics

Megabonk
Shared: Bullet Hell · Action Roguelike · Action

20 Minutes Till Dawn
Shared: Bullet Hell · Action Roguelike · Survival

Death Must Die
Shared: Bullet Hell · Action Roguelike · Action

Enter the Gungeon
Shared: Bullet Hell · Action Roguelike · Pixel Graphics

Skul: The Hero Slayer
Shared: Action · Indie · Action Roguelike

Nuclear Throne
Shared: Bullet Hell · Action · Action Roguelike

Boneraiser Minions
Shared: Bullet Hell · Action Roguelike · Pixel Graphics

BALL x PIT
Shared: Action · Bullet Hell · Action Roguelike

Brotato
Shared: Bullet Hell · Action Roguelike · Survival

Gensokyo Night Festival
Shared: Action · Indie · Casual

Halls of Torment
Shared: Bullet Hell · Action Roguelike · Action

Rocket Rats
Shared: Bullet Hell · Casual · Action Roguelike

Noobs Want to Live
Shared: Bullet Hell · Action · Casual

Asgard's Fall — Viking Survivors
Shared: Bullet Hell · Casual · Action Roguelike

Timberman
Shared: Casual · Action · Indie

Arms of God
Shared: Bullet Hell · Action · Action Roguelike

Atomicrops
Shared: Action · Bullet Hell · Action Roguelike

Desktop Survivors 98
Shared: Bullet Hell · Action · Casual

The Binding of Isaac: Rebirth
Shared: Action Roguelike · Indie · Pixel Graphics

Seraph's Last Stand
Shared: Bullet Hell · Casual · Action Roguelike

Tower of Babel: Survivors of Chaos
Shared: Bullet Hell · Action · Action Roguelike

Dungreed
Shared: Action · Action Roguelike · Pixel Graphics

BlazBlue Entropy Effect
Shared: Action · Action Roguelike · Pixel Graphics