Games like Heat Guardian
Games like Heat Guardian include Rain World, RUINER, We Happy Few, Deadlight, and Escape From Duckov. We matched them by the tags players give Heat Guardian on Steam (Action, Indie, Survival, Atmospheric, and Top-Down Shooter): closest matches first, and among equally close ones the better-known games.

Rain World
Shared: Survival · Atmospheric · Indie

RUINER
Shared: Action · Indie · Top-Down Shooter

We Happy Few
Shared: Action · Survival · Indie

Deadlight
Shared: Action · Indie · Atmospheric

Escape From Duckov
Shared: Action · Top-Down Shooter · Survival

The Forest
Shared: Survival · Action · Atmospheric

Green Hell
Shared: Survival · Action · Indie

Outlast
Shared: Atmospheric · Survival · Action

The Final Station
Shared: Survival · Indie · Action

The Last Stand: Aftermath
Shared: Survival · Top-Down Shooter · Action

Nation Red
Shared: Action · Indie · Top-Down Shooter

The Long Dark
Shared: Survival · Atmospheric · Indie

Feed and Grow: Fish
Shared: Survival · Action · Indie

12 is Better Than 6
Shared: Action · Indie · Top-Down Shooter

Hotline Miami
Shared: Action · Indie · Top-Down Shooter

Deliver Us The Moon
Shared: Indie · Action · Atmospheric

Don't Starve Together
Shared: Survival · Indie · Atmospheric

SYNTHETIK: Legion Rising
Shared: Indie · Action · Top-Down Shooter

METRO Last Light Redux
Shared: Action · Atmospheric · Survival

PUBG: BATTLEGROUNDS
Shared: Survival · Action

Sir, You Are Being Hunted
Shared: Survival · Indie · Action

Pacific Drive
Shared: Survival · Atmospheric · Action

This War of Mine
Shared: Survival · Atmospheric · Indie

Guardians of Orion (Phase 2)
Shared: Action · Indie · Survival