Games like Mission IDLE
Games like Mission IDLE include Cookie Clicker, Click the Button, Travellers Rest, Your Chronicle, and Click Mage. We matched them by the tags players give Mission IDLE on Steam (Casual, Incremental, Collectathon, Text-Based, and Cartoony): closest matches first, and among equally close ones the better-known games.

Cookie Clicker
Shared: Incremental · Casual · Pixel Graphics

Click the Button
Shared: Casual · Incremental · Pixel Graphics

Travellers Rest
Shared: Pixel Graphics · Medieval · Collectathon

Your Chronicle
Shared: Incremental · Text-Based · Collectathon

Click Mage
Shared: Incremental · Casual · Pixel Graphics

Proverbs
Shared: Casual · Collectathon · Incremental

DAVE THE DIVER
Shared: Casual · Pixel Graphics · Singleplayer

Digseum
Shared: Casual · Incremental · Pixel Graphics

Librarian: Tidy Up the Arcane Library!
Shared: Collectathon · Casual · Singleplayer

Kingdom Rush - Tower Defense
Shared: Casual · Fantasy · Singleplayer

Timberman
Shared: Casual · Pixel Graphics · Incremental

Keep on Mining!
Shared: Incremental · Casual · Singleplayer

Shelldiver
Shared: Casual · Incremental · Pixel Graphics

Kingdom Rush Origins - Tower Defense
Shared: Casual · Singleplayer · Cartoony

Idle Champions of the Forgotten Realms
Shared: Incremental · Fantasy · Casual

Cauldron
Shared: Incremental · Casual · Pixel Graphics

Touhou Mystia's Izakaya
Shared: Casual · Pixel Graphics · Incremental

Keep on Mining! - Worlds
Shared: Casual · Incremental · Collectathon

Horripilant
Shared: Incremental · Casual · Pixel Graphics

Fortune Mill
Shared: Incremental · Casual · Pixel Graphics

Click and Conquer
Shared: Casual · Incremental · Pixel Graphics

The Adventure of NAYU
Shared: Casual · Incremental · Fantasy

Unfair Flips
Shared: Casual · Incremental · Pixel Graphics

Kin and Quarry
Shared: Casual · Incremental · Pixel Graphics