Games like 1-DC
Games like 1-DC include Opus Magnum, Little Nightmares II, People Playground, LIMBO, and while True: learn(). We matched them by the tags players give 1-DC on Steam (Programming, Simulation, Puzzle, Sandbox, and Dark): closest matches first, and among equally close ones the better-known games.

Opus Magnum
Shared: Programming · Puzzle · Simulation

Little Nightmares II
Shared: Puzzle · Dark · Atmospheric

People Playground
Shared: Sandbox · Simulation · 2D

LIMBO
Shared: Puzzle · Dark · Atmospheric

while True: learn()
Shared: Programming · Simulation · Puzzle

Poppy Playtime
Shared: Puzzle · Dark · Singleplayer

Sally Face - Episode One
Shared: Puzzle · Psychological Horror · Dark

Little Nightmares
Shared: Atmospheric · Puzzle · Dark

Bridge Constructor Portal
Shared: Simulation · Puzzle · Level Editor

Poly Bridge
Shared: Simulation · Puzzle · Sandbox

SHENZHEN I/O
Shared: Programming · Puzzle · Simulation

s.p.l.i.t
Shared: Simulation · Atmospheric · Psychological Horror

Firework
Shared: Puzzle · Atmospheric · Psychological Horror

Fran Bow
Shared: Puzzle · Psychological Horror · Dark

Papers, Please
Shared: Simulation · Puzzle · Singleplayer

Baba Is You
Shared: Puzzle · Programming · Singleplayer

SOMA
Shared: Atmospheric · Psychological Horror · Dark

Strange Horticulture
Shared: Puzzle · Dark · Simulation

Mini Metro
Shared: Puzzle · Simulation · Minimalist

Hacknet
Shared: Simulation · Programming · Atmospheric

Uplink
Shared: Simulation · Programming · Puzzle

鬼谷八荒 Tale of Immortal
Shared: Simulation · Sandbox · Singleplayer

The Farmer Was Replaced
Shared: Programming · Puzzle · Simulation

Car Mechanic Simulator 2021
Shared: Simulation · Sandbox · Puzzle