The ‘Craft’ Minecraft core in RetroArch is a simple Minecraft clone packed in to a RetroArch core.
It allows players to move around freely in a creative game mode, where you can explore and build freely.
A number of elements have been introduced to the Craft core including Biomes, water, more than 20 block variations. simple cloud graphics, day & night cycles and a textured sky dome.
There are also some nice graphical touches includes sunrise/sunset colour blending, ambient occlusion for shading and a configurable draw distance to optimise framerates.
The original Craft project was developed by Michael Fogleman and you can find his project here.
All in all, the Craft core is very limited, but just a fun project port that is more of a tech demo than anything else.