Easiest Game Servers to self-host

Tower-defense and factory game with servers

Replaces Factorio

Containerized Minecraft Java server image

Replaces Minecraft Realms

Self-hostable browser version of the 2048 sliding puzzle

Replaces Mobile puzzle games

Open-source reimplementation of Civilization V

Replaces Civilization V

Open-source Minecraft launcher for managing instances and modpacks

Replaces Official Minecraft Launcher, CurseForge app

Self-hostable HTML5 multiplayer adventure game

Replaces Realm of the Mad God

Open-source transport simulation game with servers

Replaces Transport Tycoon

Free space exploration and trading game

Replaces Escape Velocity

Open-source factory-building puzzle game

Replaces Factorio

Turn-based fantasy strategy with multiplayer server

Replaces Heroes of Might and Magic

Visual novel engine for creating story-based games

Replaces TyranoBuilder

Free 3D kart racing game with online servers

Replaces Mario Kart

In-game map editor for Minecraft single-player and servers

Replaces commercial map editing tools

Classic-style 2D side-scrolling platform game

Replaces Super Mario Bros

Open-source tool for telling interactive nonlinear stories

Replaces Inklewriter

Retro 2D multiplayer shooter with servers

Replaces Worms, Soldat

Self-hosted block-stacking puzzle game in the browser

Replaces Tetris

Essential commands and tools plugin for Minecraft servers

Replaces commercial server management plugins

Free city-building simulation game

Replaces SimCity

Open-source space adventure and trading simulator

Replaces Elite, Frontier

Docker image for running Minecraft Bedrock Edition servers

Replaces Minecraft Realms

Free open-source control panel for self-hosted game servers

Replaces AMP, Pterodactyl

Open-source interpreter for RPG Maker 2000 and 2003 games

Replaces RPG Maker RTP runtime

Browser idle and incremental game host

Replaces Cookie Clicker, Universal Paperclips

Lightweight multiplayer first-person shooter

Replaces Counter-Strike

Self-hosted analytics plugin for Minecraft servers

Replaces Commercial game analytics

Open-source 2D space trading and combat game

Replaces Escape Velocity

Implementation of Terraforming Mars board game

Cooperative platformer based on Teeworlds

Replaces Teeworlds

Open-source turn-based colonization strategy game

Replaces Sid Meier's Colonization

Fast-paced free arena first-person shooter

Replaces Quake, Unreal Tournament

Sandbox voxel game with multiplayer servers

Replaces Minecraft

Open-source city building and management game

Replaces SimCity

Turn-based artillery strategy game with servers

Replaces Worms

Open-source dungeon-keeper-style real-time strategy game

Replaces Dungeon Keeper

Open-source multiplayer action and tactics game

Replaces Clonk

Fast-paced real-time strategy game for the Linux terminal

Replaces commercial RTS games

Open-source voxel sandbox game for Luanti

Replaces Minecraft

3D Tron-style lightcycle multiplayer game

Replaces Tron

Free Quake III-style arena shooter with servers

Replaces Quake III Arena

Open-source strategy game of defending Earth from aliens

Replaces XCOM

Free Lemmings-inspired puzzle game with network multiplayer

Replaces Lemmings

Open-source transport and economy simulation game

Replaces Transport Tycoon

Server hosting tool for Minecraft and other multiplayers

Gameboy in your browser

2048 game clone in 3D

2048 variant with Euro coins and notes

2048 game clone

Set of games Framagames from Framasoft

Wordle-based online word game