Games like Relativity Wars - A Science Space RTS
Games like Relativity Wars - A Science Space RTS include Kerbal Space Program, Totally Accurate Battle Simulator, Between the Stars, The Scroll of Taiwu : Beyond The Dome, and Home Behind 2. We matched them by the tags players give Relativity Wars - A Science Space RTS on Steam (Strategy, Indie, Simulation, RTS, and Adventure): closest matches first, and among equally close ones the better-known games.

Kerbal Space Program
Shared: Simulation · Space · Physics

Totally Accurate Battle Simulator
Shared: Simulation · Strategy · Indie

Between the Stars
Shared: Simulation · Indie · Strategy

The Scroll of Taiwu : Beyond The Dome
Shared: Strategy · RPG · Indie

Home Behind 2
Shared: Strategy · Indie · Adventure

Mount & Blade II: Bannerlord
Shared: Strategy · RPG · Simulation

Space Rangers HD: A War Apart
Shared: Strategy · Simulation · RPG

Space Pirates And Zombies 2
Shared: Strategy · Indie · Space

FTL: Faster Than Light
Shared: Strategy · Indie · Space

Sultan's Game
Shared: Strategy · Simulation · RPG

The Long Journey Home
Shared: Strategy · Simulation · Indie

Home Behind
Shared: Indie · Adventure · RPG

Crusader Kings III
Shared: Strategy · Simulation · RPG

Universe Sandbox
Shared: Simulation · Space · Physics

Celestial Command
Shared: Indie · Simulation · Strategy

Total War: WARHAMMER
Shared: Strategy · Simulation · RPG

Empyrion - Galactic Survival
Shared: Simulation · Space · Indie

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

Objects in Space
Shared: Indie · Simulation · Strategy

Rebel Galaxy
Shared: Space · RPG · Adventure

Starpoint Gemini Warlords
Shared: Strategy · Simulation · RPG

Sands of Salzaar
Shared: Strategy · Indie · RPG

EVE Online
Shared: Adventure · Simulation · Space Sim

Plague Inc: Evolved
Shared: Strategy · Simulation · Indie