Games like Tamageddon
Games like Tamageddon include Megabonk, Vampire Survivors, Hades, The Binding of Isaac, and 20 Minutes Till Dawn. We matched them by the tags players give Tamageddon on Steam (Action, Action Roguelike, Bullet Hell, 3D, and Combat): closest matches first, and among equally close ones the better-known games.

Megabonk
Shared: Action Roguelike · Bullet Hell · Action

Vampire Survivors
Shared: Action Roguelike · Bullet Hell · Singleplayer

Hades
Shared: Action Roguelike · Action · Indie

The Binding of Isaac
Shared: Action Roguelike · Action · Indie

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

Enter the Gungeon
Shared: Action Roguelike · Bullet Hell · Indie

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

Black Myth: Wukong
Shared: Action · Combat · Singleplayer

Deep Rock Galactic: Survivor
Shared: Action Roguelike · Bullet Hell · Action

Brotato
Shared: Bullet Hell · Action Roguelike · Singleplayer

Soulstone Survivors
Shared: Action Roguelike · Bullet Hell · Action

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

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

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

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

Project Lazarus
Shared: Action · Action Roguelike · Bullet Hell

Nuclear Throne
Shared: Action Roguelike · Action · Bullet Hell

The Binding of Isaac: Rebirth
Shared: Action Roguelike · Indie · Singleplayer

Windowkill
Shared: Action · Action Roguelike · Bullet Hell

Magicraft
Shared: Action Roguelike · Bullet Hell · Action

Goobies
Shared: Action Roguelike · Bullet Hell · 3D

Atomicrops
Shared: Action · Bullet Hell · Action Roguelike

Twilight Survivors
Shared: Action Roguelike · Bullet Hell · Action

God Of Weapons
Shared: Action Roguelike · Bullet Hell · Procedural Generation