Games like KaBoom!
Games like KaBoom! include Vampire Survivors, Geometry Dash, DJMAX RESPECT V, A Dance of Fire and Ice, and Bit Blaster XL. We matched them by the tags players give KaBoom! on Steam (Action, Casual, Arcade, Rhythm, and Bullet Hell): closest matches first, and among equally close ones the better-known games.

Vampire Survivors
Shared: Bullet Hell · Casual · Pixel Graphics

Geometry Dash
Shared: Rhythm · 2D · Precision Platformer

DJMAX RESPECT V
Shared: Casual · Rhythm · Action

A Dance of Fire and Ice
Shared: Rhythm · Arcade · 2D

Bit Blaster XL
Shared: Bullet Hell · Arcade · Action

Muse Dash
Shared: Rhythm · Casual · Cute

Planes, Bullets and Vodka
Shared: Action · Casual · Arcade

Rhythm Doctor
Shared: Rhythm · Action · Pixel Graphics

pureya
Shared: Casual · Arcade · 2D

Teenage Mutant Ninja Turtles: Shredder's Revenge
Shared: Side Scroller · Arcade · Action

Broforce
Shared: Action · Pixel Graphics · 2D

Timberman
Shared: Casual · Action · Arcade

LUFTRAUSERS
Shared: Action · Arcade · Bullet Hell

Beat Hazard
Shared: Rhythm · Bullet Hell · Action

Sixtar Gate: STARTRAIL
Shared: Action · Casual · Arcade

Cyberhunt
Shared: Action · Casual · Arcade

BALL x PIT
Shared: Action · Arcade · Bullet Hell

Twin Shot Deluxe
Shared: Action · Casual · Arcade

Downwell
Shared: Precision Platformer · Arcade · Action

UFO 50
Shared: Action · Arcade · Pixel Graphics

Super Bit Blaster XL
Shared: Bullet Hell · Arcade · Action

Huntdown
Shared: Action · Side Scroller · Pixel Graphics

Sonic Mania
Shared: 2D · Action · Pixel Graphics

MARVEL Cosmic Invasion
Shared: Arcade · Action · Side Scroller