Games like Combat Survivors
Games like Combat Survivors include Risk of Rain 2, Hades, Skul: The Hero Slayer, The Binding of Isaac, and Nuclear Throne. We matched them by the tags players give Combat Survivors on Steam (Action, Action Roguelike, Shooter, Roguelike, and 3D Fighter): closest matches first, and among equally close ones the better-known games.

Risk of Rain 2
Shared: Action Roguelike · Action · Roguelike

Hades
Shared: Action Roguelike · Action · Indie

Skul: The Hero Slayer
Shared: Action · Action Roguelike · Indie

The Binding of Isaac
Shared: Action Roguelike · Roguelike · Indie

Nuclear Throne
Shared: Action Roguelike · Roguelike · Action

Megabonk
Shared: Action Roguelike · Roguelike · Action

Hades II
Shared: Action · Roguelike · Action Roguelike

The Binding of Isaac: Rebirth
Shared: Action Roguelike · Roguelike · Indie

Enter the Gungeon
Shared: Action Roguelike · Roguelike · Indie

BPM: BULLETS PER MINUTE
Shared: Action · Roguelike · Shooter

Gunfire Reborn
Shared: Roguelike · Action · Action Roguelike

Risk of Rain (2013)
Shared: Action Roguelike · Roguelike · Action

Vampire Survivors
Shared: Action Roguelike · Indie · Roguelike

Rogue Legacy
Shared: Action Roguelike · Roguelike · Action

SYNTHETIK: Legion Rising
Shared: Action · Action Roguelike · Indie

Ravenswatch
Shared: Action Roguelike · Roguelike · Action

Roboquest
Shared: Action Roguelike · Shooter · Action

Crab Champions
Shared: Action Roguelike · Roguelike · Shooter

EVERSPACE™
Shared: Action Roguelike · Action · Indie

Dungreed
Shared: Action Roguelike · Action · Roguelike

Heavy Bullets
Shared: Action · Action Roguelike · Indie

Clone Drone in the Danger Zone
Shared: Action · 3D Fighter · Indie

Juicy Realm
Shared: Action · Action Roguelike · Indie

Wizard of Legend
Shared: Action Roguelike · Roguelike · Action