Version 6 has already finished and released. The ultimate rare card will be Atlas which supports 9000 health!
The evil animals will also arrive in this version, and the other new cards such as Saturn Saw, Dirty Fighters and more. Evil Aura is also introduced here. Note that the Atlas here doesn't have the ability like the Version 7 does.
Note: This is the last version for the current English version of AK, but don't worry as the new AK series will launch.