This is a "Magic 1994 Time Walk" Cube, build of Revised and The Dark Cards. The paper version of the cube works with a fix rarity distribution for the packs: each pack contains 4 rares, 5 uncommons and 6 commons. The cube runs "dual lands", which are an exception regarding their rarity slot in the packs: they come as common instead of rare.
The cube is played with up to date rules except two "old" rules, to enhence the "time walk feeling":