Games like Rainbow Reactor
Games like Rainbow Reactor include A Dance of Fire and Ice, Beat Saber, Geometry Dash, AudioSurf, and Ragnarock. We matched them by the tags players give Rainbow Reactor on Steam (Action, Match 3, Arcade, Music, and Rhythm): closest matches first, and among equally close ones the better-known games.

A Dance of Fire and Ice
Shared: Music · Rhythm · Arcade

Beat Saber
Shared: VR · Music · Rhythm

Geometry Dash
Shared: Music · Rhythm · Colorful

AudioSurf
Shared: Music · Rhythm · Arcade

Ragnarock
Shared: Action · Rhythm · Music

DJMAX RESPECT V
Shared: Action · Music · Rhythm

Pistol Whip
Shared: VR · Action · Arcade

Hatsune Miku: Project DIVA Mega Mix+
Shared: Arcade · Rhythm · Action

Sayonara Wild Hearts
Shared: Action · Music · Rhythm

Zuma Deluxe
Shared: Match 3 · Arcade · Casual

EZ2ON REBOOT : R
Shared: Action · Rhythm · Music

Muse Dash
Shared: Music · Rhythm · Casual

Rhythm Doctor
Shared: Music · Rhythm · Action

Zuma's Revenge!
Shared: Action · Match 3 · Casual

Spin Rhythm XD
Shared: Music · Rhythm · Action

Rift of the NecroDancer
Shared: Music · Rhythm · Action

Music Racer
Shared: Music · Action · Rhythm

BOXVR
Shared: Action · VR · Casual

Super Hexagon
Shared: Arcade · Rhythm · Action

Audiosurf 2
Shared: Music · Rhythm · Arcade

BARRIER X
Shared: Action · Arcade · Music

LUMINES REMASTERED
Shared: Action · Music · Casual

Thumper
Shared: Action · Rhythm · VR

Dead as Disco
Shared: Rhythm · Music · Action

