Games like Starscape
Games like Starscape include Heat Signature, FTL: Faster Than Light, Space Pirates and Zombies, Reassembly, and Aliens: Dark Descent. We matched them by the tags players give Starscape on Steam (Action, Indie, Strategy, Space, and Top-Down): closest matches first, and among equally close ones the better-known games.

Heat Signature
Shared: Indie · Space · Action

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

Space Pirates and Zombies
Shared: Action · Indie · Space

Reassembly
Shared: Space · Strategy · Action

Aliens: Dark Descent
Shared: Action · Strategy · Sci-fi

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

ENDLESS Space™ 2
Shared: Strategy · Space · Sci-fi

STAR WARS™ Empire at War - Gold Pack
Shared: Strategy · Space · Sci-fi

Infested Planet
Shared: Action · Strategy · Indie

Deliver Us The Moon
Shared: Indie · Action · Space

Door Kickers
Shared: Strategy · Action · Top-Down

Stellaris
Shared: Strategy · Space · Sci-fi

Satellite Reign
Shared: Action · Strategy · Indie

X-Morph: Defense
Shared: Action · Strategy · Indie

Space Run
Shared: Strategy · Indie · Space

Space Crew: Legendary Edition
Shared: Action · Strategy · Sci-fi

Between the Stars
Shared: Action · Space · Indie

Natural Selection 2
Shared: Strategy · Action · Indie

EVERSPACE™
Shared: Action · Space · Indie

Starcom: Nexus
Shared: Space · Action · Sci-fi

Hotline Miami
Shared: Action · Indie · Top-Down

House of the Dying Sun
Shared: Action · Indie · Space

Halo: Spartan Assault
Shared: Action · Sci-fi · Top-Down

Cosmoteer: Starship Architect & Commander
Shared: Sci-fi · Space · Indie