Games like Invasion
Games like Invasion include Warhammer 40,000: Space Marine 2, Grand Theft Auto V Legacy, Resident Evil Requiem, Atomic Heart, and STAR WARS Jedi: Survivor™. We matched them by the tags players give Invasion on Steam (Action, Indie, Adventure, FPS, and Action-Adventure): closest matches first, and among equally close ones the better-known games.

Warhammer 40,000: Space Marine 2
Shared: Action · Adventure · Third-Person Shooter

Grand Theft Auto V Legacy
Shared: Action · Adventure · First-Person

Resident Evil Requiem
Shared: Action · FPS · Third-Person Shooter

Atomic Heart
Shared: Adventure · Action · FPS

STAR WARS Jedi: Survivor™
Shared: Action · Adventure · Action-Adventure

Half-Life 2
Shared: Action · FPS · Adventure

Black Mesa
Shared: Action · FPS · First-Person

Rise of the Tomb Raider™
Shared: Action · Adventure · Action-Adventure

Tomb Raider Game of the Year
Shared: Action · Adventure · Third Person

PRAGMATA
Shared: Action · Adventure · Third-Person Shooter

STAR WARS™ Battlefront™ II
Shared: Action · Third-Person Shooter · FPS

STAR WARS™ Battlefront II (Classic, 2005)
Shared: Action · Third-Person Shooter · FPS

Star Wars Outlaws
Shared: Action · Adventure · Action-Adventure

BioShock Infinite
Shared: Action · FPS · Adventure

Far Cry® 6
Shared: FPS · Action · Action-Adventure

Aimlabs
Shared: FPS · Action · Third-Person Shooter

Halo Infinite
Shared: FPS · Action · First-Person

ORION: Prelude
Shared: Action · FPS · Adventure

High On Life
Shared: FPS · Adventure · Action-Adventure

Far Cry 3
Shared: Action · FPS · Adventure

PUBG: BATTLEGROUNDS
Shared: FPS · Action · Third-Person Shooter

Bright Memory: Infinite
Shared: Action · Indie · FPS

Bright Memory
Shared: FPS · Action · First-Person

Half-Life: Opposing Force
Shared: Action · FPS · Adventure