Games like Ordinary Defenders
Games like Ordinary Defenders include Age of Darkness: Final Stand, Creeper World 3: Arc Eternal, The King is Watching, Age of Empires II (Retired), and Stronghold: Definitive Edition. We matched them by the tags players give Ordinary Defenders on Steam (Tower Defense, Economy, Simulation, RTS, and Base Building): closest matches first, and among equally close ones the better-known games.

Age of Darkness: Final Stand
Shared: Tower Defense · RTS · Base Building

Creeper World 3: Arc Eternal
Shared: Tower Defense · RTS · Strategy

The King is Watching
Shared: Tower Defense · Base Building · RTS

Age of Empires II (Retired)
Shared: RTS · Strategy · Medieval

Stronghold: Definitive Edition
Shared: RTS · Economy · Strategy

Kingdom Two Crowns
Shared: Tower Defense · Base Building · Medieval

Foundation
Shared: Simulation · Medieval · Strategy

Mindustry
Shared: Tower Defense · Base Building · RTS

Crusader Kings III
Shared: Simulation · Medieval · Strategy

They Are Billions
Shared: Base Building · Tower Defense · RTS

Diplomacy is Not an Option
Shared: Medieval · Base Building · RTS

Farthest Frontier
Shared: Economy · Strategy · Medieval

Manor Lords
Shared: Simulation · Base Building · Strategy

Dungeons 3
Shared: Simulation · Base Building · RTS

Warpips
Shared: Tower Defense · RTS · Strategy

Becastled
Shared: Base Building · RTS · Strategy

Stronghold HD (2012)
Shared: Economy · Tower Defense · Medieval

The Riftbreaker
Shared: Tower Defense · Base Building · Simulation

Stronghold Crusader: Definitive Edition
Shared: Strategy · Tower Defense · Medieval

Anno 1800
Shared: Simulation · Economy · Strategy

Rise to Ruins
Shared: Tower Defense · Base Building · Strategy

Workers & Resources: Soviet Republic
Shared: Simulation · Base Building · Strategy

Kingdoms and Castles
Shared: Simulation · Economy · Strategy

Border Pioneer
Shared: Tower Defense · Base Building · Strategy