Games like Midnight Gunwatch
Games like Midnight Gunwatch include Orcs Must Die! 3, Zombieville USA 3D, Halo: Spartan Assault, X-Morph: Defense, and Thronefall. We matched them by the tags players give Midnight Gunwatch on Steam (Top-Down Shooter, Strategy, Tower Defense, PvE, and Action): closest matches first, and among equally close ones the better-known games.

Orcs Must Die! 3
Shared: Tower Defense · Strategy · PvE

Zombieville USA 3D
Shared: Top-Down Shooter · Action · Arcade

Halo: Spartan Assault
Shared: Top-Down Shooter · Action · Strategy

X-Morph: Defense
Shared: Strategy · Tower Defense · Action

Thronefall
Shared: Strategy · Tower Defense · Action

Cluckmech Oasis
Shared: Strategy · Tower Defense · Top-Down Shooter

Yet Another Zombie Defense HD
Shared: Top-Down Shooter · Tower Defense · Strategy

The Last Stand: Aftermath
Shared: Top-Down Shooter · Shooter · Post-apocalyptic

Bloons TD 6
Shared: Strategy · Tower Defense · 3D

Children of the Sun
Shared: Strategy · Action · Shooter

Lumencraft
Shared: Strategy · Action · Tower Defense

Ash & Adam's Existential Treads
Shared: Strategy · Tower Defense · Action

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

Plants vs. Zombies GOTY Edition
Shared: Tower Defense · Strategy · Zombies

Sanctum 2
Shared: Tower Defense · Strategy · Action

Orcs Must Die! 2
Shared: Tower Defense · Strategy · Action

Orcs Must Die!
Shared: Tower Defense · Strategy · Action

Age of Darkness: Final Stand
Shared: Tower Defense · Strategy · PvE

Police Stories
Shared: Strategy · Action · Top-Down Shooter

The Ascent
Shared: Top-Down Shooter · Action · Shooter

PUBG: BATTLEGROUNDS
Shared: Shooter · Action · Strategy

GemCraft - Chasing Shadows
Shared: Strategy · Tower Defense · Action

Yet Another Zombie Survivors
Shared: Top-Down Shooter · Arcade · Indie

10 Miles To Safety
Shared: Strategy · Action · Top-Down Shooter