Sorry but, you got a few seasons mixed up.
Juggernaut was s1, as well as berserker (if memory serves me right)
Demon lord was s2
Champion and Nobel was s4
Arch was season 5
Imbound was arguably season 7 (apparently it was a new season when planar Tomb arrived)
So Gretta would be s8
Anti and banished will be season 9...