Solarus Action-RPG game engine - Solarus is a free and open-source Action-RPG game engine.
Godot Engine - Feature-packed 2D and 3D open source game engine.
EasyRPG - RPG Maker 2000 and RPG Maker 2003 compatible replacement.
GDevelop - GDevelop is an open-source game making software designed to be used by everyone.
Open RPG Maker - Open RPG Maker is a free and open source clone of features from the RPG Maker series (i.e.
Unity - The multiplatform game creation tools for everyone.