Inspired by the core gameplay of Minecraft, the name MineClone2 was not a particularly good one and it seems the developers were aware and so it's gone through a rebrand to be now called VoxeLibre.
Built on the free and open source Minetest game engine, it's one of the most popular voxel sandbox open-world games around as an alternative to Minecraft. As they announced on their Git page about the renaming