Games like middenmoon
Games like middenmoon include Oxygen Not Included, Prison Architect, Dyson Sphere Program, RimWorld, and Factorio. We matched them by the tags players give middenmoon on Steam (Sandbox, 2D, Simulation, Top-Down, and Sci-fi): closest matches first, and among equally close ones the better-known games.

Oxygen Not Included
Shared: 2D · Sandbox · Singleplayer

Prison Architect
Shared: Sandbox · Simulation · 2D

Dyson Sphere Program
Shared: Simulation · Automation · Sandbox

RimWorld
Shared: Sandbox · Simulation · Singleplayer

Factorio
Shared: Sandbox · Automation · Base Building

People Playground
Shared: Sandbox · 2D · Simulation

Potion Craft: Alchemist Simulator
Shared: Simulation · Singleplayer · 2D

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

shapez
Shared: Sandbox · Automation · Singleplayer

The Last Caretaker
Shared: Sandbox · Singleplayer · Automation

Totally Accurate Battle Simulator
Shared: Sandbox · Simulation · Singleplayer

Spaceflight Simulator
Shared: Sandbox · Simulation · 2D

Game Dev Tycoon
Shared: Simulation · Indie · 2D

Airport CEO
Shared: Simulation · Singleplayer · Sandbox

Hydroneer
Shared: Sandbox · Automation · Base Building

River Town Factory
Shared: Sandbox · Simulation · Automation

Kerbal Space Program
Shared: Sandbox · Simulation · Indie

Satisfactory
Shared: Sandbox · Automation · Base Building

Mindustry
Shared: Sandbox · Automation · 2D

Creeper World 3: Arc Eternal
Shared: Indie · Sci-fi · Singleplayer

Space Engineers
Shared: Sandbox · Simulation · Singleplayer

Spacebase DF-9
Shared: Simulation · Sandbox · Sci-fi

Production Line : Car factory simulation
Shared: Simulation · Sandbox · Automation

Reus
Shared: Simulation · Sandbox · Indie