Games like Senpai Arena
Games like Senpai Arena include Left 4 Dead 2, DayZ, Left 4 Dead, Resident Evil 4, and Resident Evil 4 (2005). We matched them by the tags players give Senpai Arena on Steam (Zombies, Real Time Tactics, Action, Arena Shooter, and Colorful): closest matches first, and among equally close ones the better-known games.

Left 4 Dead 2
Shared: Zombies · Action · Survival

DayZ
Shared: Zombies · Survival · Action

Left 4 Dead
Shared: Zombies · Action · Survival

Resident Evil 4
Shared: Action · Zombies · Survival

Resident Evil 4 (2005)
Shared: Zombies · Action · Third-Person Shooter

The Last of Waifus
Shared: Action · Zombies · Arena Shooter

Sunset Overdrive
Shared: Action · Character Customization · Zombies

Resident Evil 6
Shared: Zombies · Action · Third-Person Shooter

World War Z
Shared: Zombies · Action · Shooter

Killing Floor 2
Shared: Zombies · Action · Shooter

Days Gone
Shared: Zombies · Action · Survival

Zombie Army Trilogy
Shared: Zombies · Action · Survival

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

Pixel Gun 3D: PC Edition
Shared: Action · Character Customization · Arena Shooter

PUBG: BATTLEGROUNDS
Shared: Action · Survival · Shooter

Resident Evil 3
Shared: Zombies · Action · Third-Person Shooter

The Last of Us™ Part I
Shared: Zombies · Survival · Shooter

Nova Drift
Shared: Shoot 'Em Up · Arena Shooter · Action

Resident Evil Revelations 2
Shared: Zombies · Action · Survival

Resident Evil 2
Shared: Zombies · Action · Survival

Resident Evil 5
Shared: Zombies · Action · Third-Person Shooter

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

Dying Light
Shared: Zombies · Action · Survival

Sword Art Online: Fatal Bullet
Shared: Action · Character Customization · Anime