Games like Rainbow Run
Games like Rainbow Run include Clustertruck, UFO 50, Rock 'N' Roll Defense, Timberman, and Game Dev Tycoon. We matched them by the tags players give Rainbow Run on Steam (Action, Casual, Indie, Strategy, and 3D Platformer): closest matches first, and among equally close ones the better-known games.

Clustertruck
Shared: Action · 3D Platformer · Indie

UFO 50
Shared: Indie · Action · Strategy

Rock 'N' Roll Defense
Shared: Casual · Action · Strategy

Timberman
Shared: Casual · Indie · Action

Game Dev Tycoon
Shared: Indie · Casual · Strategy

Plague Inc: Evolved
Shared: Strategy · Indie · Casual

ShellShock Live
Shared: Action · Strategy · Casual

Minimalism
Shared: Casual · Action · Indie

Caster
Shared: Action · Indie · Casual

Touhou Big Big Battle
Shared: Indie · Strategy · Casual

Dota 2
Shared: Strategy · Action · Difficult

Deadly Days
Shared: Action · Indie · Casual

Plebby Quest: The Crusades
Shared: Casual · Strategy · Indie

Achievement Clicker
Shared: Casual · Indie · Action

Overdungeon
Shared: Indie · Strategy · Casual

Kao the Kangaroo: Round 2 (2003 re-release)
Shared: Action · Casual · 3D Platformer

Waveform
Shared: Indie · Casual · Strategy

Kingdom Rush - Tower Defense
Shared: Strategy · Casual · Action

Mineirinho Director's Cut
Shared: Action · Indie · Difficult

Bloons TD 5
Shared: Strategy · Action · Casual

Total Tank Simulator
Shared: Action · Strategy · Indie

s&box
Shared: Casual · Action · 3D Platformer

A Dance of Fire and Ice
Shared: Indie · Difficult · Casual

Kingdom Rush Origins - Tower Defense
Shared: Strategy · Casual · Difficult