Games like Lock Down
Games like Lock Down include Left 4 Dead 2, Counter-Strike 2, Left 4 Dead, Half-Life: Alyx, and Resident Evil Requiem. We matched them by the tags players give Lock Down on Steam (Horror, Team-Based, Shooter, Action, and Sci-fi): closest matches first, and among equally close ones the better-known games.

Left 4 Dead 2
Shared: Co-op · Zombies · Shooter

Counter-Strike 2
Shared: Shooter · Team-Based · Action

Left 4 Dead
Shared: Co-op · Horror · Zombies

Half-Life: Alyx
Shared: VR · Horror · Shooter

Resident Evil Requiem
Shared: Horror · Zombies · Action

Bodycam
Shared: Horror · Shooter · VR

Killing Floor
Shared: Co-op · Horror · Zombies

Call of Duty®: Black Ops III
Shared: Shooter · Zombies · Action

Apex Legends™
Shared: Shooter · Action · Team-Based

GTFO
Shared: Horror · Co-op · Shooter

Pavlov
Shared: VR · Shooter · Action

Ready or Not
Shared: Shooter · Co-op · Horror

Dying Light
Shared: Horror · Zombies · Survival Horror

PUBG: BATTLEGROUNDS
Shared: Shooter · Action · Co-op

Back 4 Blood
Shared: Zombies · Co-op · Shooter

Killing Floor 3
Shared: Co-op · Horror · Shooter

Resident Evil 5
Shared: Co-op · Horror · Action

Resident Evil 4
Shared: Horror · Action · Zombies

Resident Evil Village
Shared: Horror · Action · VR

Dead by Daylight
Shared: Horror · Co-op · Team-Based

Resident Evil 6
Shared: Co-op · Horror · Action

Half-Life 2
Shared: Action · Sci-fi · Shooter

Phasmophobia
Shared: Horror · VR · Co-op

Arizona Sunshine® VR Legacy
Shared: VR · Horror · Action