世は正に大ゲームエンジン時代

Godot
https://godotengine.org/

Cocos
https://www.cocos.com/en

Stride
https://www.stride3d.net/

MonoGame
https://www.monogame.net/

Open 3D Engine
https://o3de.org/

Defold
https://defold.com/

GameMaker
https://gamemaker.io/

Flax
https://flaxengine.com/

Unigine
https://unigine.com/