Games like Kantmis-Zero
Games like Kantmis-Zero include Skul: The Hero Slayer, Undertale, Vampire Survivors, SANABI, and Papers, Please. We matched them by the tags players give Kantmis-Zero on Steam (Action, 2D, Multiple Endings, Boss Rush, and Pixel Graphics): closest matches first, and among equally close ones the better-known games.

Skul: The Hero Slayer
Shared: Action · 2D · Pixel Graphics

Undertale
Shared: Multiple Endings · Pixel Graphics · 2D

Vampire Survivors
Shared: 2D · Pixel Graphics · Singleplayer

SANABI
Shared: Action · Pixel Graphics · 2D

Papers, Please
Shared: Pixel Graphics · Indie · Multiple Endings

Titan Souls
Shared: Pixel Graphics · Action · Boss Rush

Five Nights at Freddy's: Into the Pit
Shared: 2D · Pixel Graphics · Singleplayer

Katana ZERO
Shared: Action · Pixel Graphics · 2D

BlazBlue Entropy Effect
Shared: 2D · Action · Pixel Graphics

Broforce
Shared: Action · 2D · Pixel Graphics

Rubinite
Shared: Boss Rush · Pixel Graphics · 2D

The Escapists
Shared: Pixel Graphics · 2D · Action

CARRION
Shared: Action · Pixel Graphics · 2D

Dome Keeper
Shared: Action · Singleplayer · Combat

Hotline Miami
Shared: Action · Pixel Graphics · Indie

Timberman
Shared: Action · Pixel Graphics · 2D

Gunpoint
Shared: 2D · Action · Pixel Graphics

Blasphemous
Shared: Pixel Graphics · 2D · Action

Reventure
Shared: Multiple Endings · Pixel Graphics · 2D

OneShot
Shared: Pixel Graphics · Indie · Singleplayer

Hollow Knight
Shared: 2D · Singleplayer · Indie

Dungeon Munchies
Shared: Action · Pixel Graphics · Indie

Shovel Knight: Treasure Trove
Shared: Pixel Graphics · 2D · Action

Terraria
Shared: 2D · Pixel Graphics · Action