Phaser is a free and fast 2D game framework for making HTML5 games
2D GPU-accelerated framework for ActionScript developers
Plugin pack for making 2D games with Bevy
A complete framework for Godot to create beautiful and complex AI
Open-source, cross-platform, game-development tools
a 2D Game Development Framework
MMORPG
A Phaser CE plugin that brings sloped tile collision handling
Build virtual reality experiences with A-Frame and React
Cocos2d for iOS and OS X, built using Objective-C
A Flash Molehill (Stage3D) GPU accelerated 2D game engine
The Flixel Power Tools are a set of plug-ins for Flixel 2.5+
Cross platform 2D game creation framework with Python bindings
Runtime graphic engine (use OpenGL) for ObjectPascal