Games like Steam Marines 2
Games like Steam Marines 2 include FTL: Faster Than Light, XCOM 2, The Scroll of Taiwu : Beyond The Dome, The Last Spell, and Sands of Salzaar. We matched them by the tags players give Steam Marines 2 on Steam (Indie, Strategy, Early Access, RPG, and Sci-fi): closest matches first, and among equally close ones the better-known games.

FTL: Faster Than Light
Shared: Strategy · Indie · Sci-fi

XCOM 2
Shared: Strategy · RPG · Singleplayer

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

The Last Spell
Shared: Strategy · RPG · Singleplayer

Sands of Salzaar
Shared: Strategy · RPG · Indie

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

Shadowrun Returns
Shared: RPG · Indie · Strategy

Dungeon of the ENDLESS™
Shared: Strategy · Indie · RPG

Fell Seal: Arbiter's Mark
Shared: Strategy · Indie · RPG

Warhammer 40,000: Mechanicus
Shared: Strategy · Sci-fi · Singleplayer

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

Chroma Squad
Shared: Strategy · RPG · Indie

觅长生
Shared: RPG · Strategy · Indie

Between the Stars
Shared: RPG · Indie · Strategy

Sultan's Game
Shared: Strategy · RPG · Singleplayer

XCOM®: Chimera Squad
Shared: Strategy · Singleplayer · Sci-fi

Transistor
Shared: Indie · Sci-fi · RPG

Darkest Dungeon®
Shared: RPG · Strategy · Singleplayer

鬼谷八荒 Tale of Immortal
Shared: Singleplayer · RPG · Tactical RPG

Into the Breach
Shared: Strategy · Indie · Sci-fi

Blackguards
Shared: Strategy · RPG · Indie

Plague Inc: Evolved
Shared: Strategy · Indie · Singleplayer

ENDLESS Legend™
Shared: Strategy · RPG · Indie

Freeman: Guerrilla Warfare
Shared: Strategy · RPG · Indie