Games like Idle Defense
Games like Idle Defense include Cookie Clicker, Banished, Totally Accurate Battle Simulator, IdleOn - The Incremental MMO, and Banana. We matched them by the tags players give Idle Defense on Steam (Strategy, Indie, Idler, Simulation, and Incremental): closest matches first, and among equally close ones the better-known games.

Cookie Clicker
Shared: Idler · Incremental · Indie

Banished
Shared: Strategy · Simulation · Indie

Totally Accurate Battle Simulator
Shared: Simulation · Strategy · Indie

IdleOn - The Incremental MMO
Shared: Idler · Incremental · Pixel Graphics

Banana
Shared: Incremental · Idler · Simulation

Tower Wizard
Shared: Idler · Strategy · Incremental

A Game About Feeding A Black Hole
Shared: Strategy · Incremental · Indie

Zero Stress King: Idle Defense
Shared: Idler · Strategy · Tower Defense

Dragon Cliff
Shared: Strategy · Idler · Incremental

Bills Must Be Paid
Shared: Strategy · Incremental · Idler

Rise to Ruins
Shared: Strategy · Tower Defense · Indie

Nodebuster
Shared: Strategy · Incremental · Idler

Foundation
Shared: Strategy · Simulation · Resource Management

Incredicer
Shared: Idler · Indie · Strategy

Fortune Mill
Shared: Idler · Incremental · Simulation

Shelldiver
Shared: Incremental · Idler · Resource Management

Click the Button
Shared: Indie · Idler · Incremental

This War of Mine
Shared: Strategy · Simulation · Singleplayer

Dawn of Man
Shared: Strategy · Simulation · Indie

Oxygen Not Included
Shared: Resource Management · Strategy · Simulation

Stardew Valley
Shared: Simulation · Pixel Graphics · Indie

Keep on Mining!
Shared: Idler · Incremental · Indie

Plague Inc: Evolved
Shared: Strategy · Indie · Simulation

The Escapists
Shared: Strategy · Indie · Simulation