Games like The Castle Doctrine
Games like The Castle Doctrine include Noita, FTL: Faster Than Light, The Binding of Isaac: Rebirth, The Escapists, and Papers, Please. We matched them by the tags players give The Castle Doctrine on Steam (Indie, Massively Multiplayer, Strategy, Perma Death, and Difficult): closest matches first, and among equally close ones the better-known games.

Noita
Shared: Indie · Difficult · Pixel Graphics

FTL: Faster Than Light
Shared: Strategy · Indie · Perma Death

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

The Escapists
Shared: Strategy · Indie · Pixel Graphics

Papers, Please
Shared: Indie · Simulation · Pixel Graphics

Baba Is You
Shared: Indie · Puzzle · Difficult

BidKing
Shared: Strategy · Massively Multiplayer · Simulation

Dungeon of the ENDLESS™
Shared: Strategy · Indie · Pixel Graphics

Mini Metro
Shared: Strategy · Indie · Puzzle

Balatro
Shared: Strategy · Indie · Roguelike

Into the Breach
Shared: Strategy · Indie · Pixel Graphics

Darkest Dungeon®
Shared: Difficult · Perma Death · Roguelike

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

Risk of Rain (2013)
Shared: Indie · Roguelike · Pixel Graphics

Game Dev Tycoon
Shared: Indie · Strategy · Simulation

Despotism 3k
Shared: Indie · Strategy · Difficult

UFO 50
Shared: Indie · Strategy · Pixel Graphics

Plague Inc: Evolved
Shared: Strategy · Indie · Simulation

The Escapists 2
Shared: Strategy · Pixel Graphics · 2D

Enter the Gungeon
Shared: Indie · Difficult · Pixel Graphics

Gunpoint
Shared: Indie · Puzzle · 2D

Slay the Spire 2
Shared: Strategy · Indie · Roguelike

Celeste
Shared: Indie · Difficult · Pixel Graphics

LIMBO
Shared: Indie · Puzzle · 2D