Games like Battle, Mushroom!
Games like Battle, Mushroom! include Vampire Survivors, Skul: The Hero Slayer, The Binding of Isaac: Rebirth, Hades, and Megabonk. We matched them by the tags players give Battle, Mushroom! on Steam (Action Roguelike, Casual, Roguelike, Action, and 2D): closest matches first, and among equally close ones the better-known games.

Vampire Survivors
Shared: Action Roguelike · 2D · Roguelike

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

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

Hades
Shared: Action Roguelike · Action · Roguelike

Megabonk
Shared: Action Roguelike · Roguelike · Indie

Rogue Legacy
Shared: Roguelike · Action Roguelike · Action

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

Dead Cells
Shared: Roguelike · Action Roguelike · 2D

Zup! S
Shared: Casual · 2D · Indie

Octogeddon
Shared: Action Roguelike · Action · Casual

Have a Nice Death
Shared: Action Roguelike · 2D · Action

Cult of the Lamb
Shared: Action Roguelike · Cute · Singleplayer

Plants vs. Zombies GOTY Edition
Shared: Casual · Singleplayer · 2D

Risk of Rain (2013)
Shared: Action Roguelike · Roguelike · Action

Dungreed
Shared: Action Roguelike · Roguelike · Action

Brotato
Shared: Roguelike · Action Roguelike · Singleplayer

Balatro
Shared: Roguelike · Singleplayer · Casual

Enter the Gungeon
Shared: Action Roguelike · Roguelike · Indie

Jianghu Survivor
Shared: Casual · Action · Action Roguelike

Kingdom Rush - Tower Defense
Shared: 2D · Singleplayer · Casual

Ballionaire
Shared: Casual · Roguelike · 2D

Hades II
Shared: Roguelike · Action · Action Roguelike

Spelunky
Shared: Action Roguelike · Roguelike · 2D

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