Alternatives to Gargoyle

GameStream client

Online multiplayer game platform

2D and 3D game engine

Frontend for emulators, game engines and media players (OpenGL graphics API)

Play most kinds of interactive fiction game files

Real-time strategy game

C# scripting capable version of Godot game engine

Tool for telling interactive, nonlinear stories

Interactive Fiction interpreter in an Electron shell

Multi-User Dungeon client

Open-source, cross-platform game engine designed to be used by everyone

Tool to run Windows games