Zeus fought Adam in the second round, and that wasnt what i meant. in the spinoff, a list of the god's fighters is revealed with only 12 combatants and the plot of the spinoff involves gods fighting for that last spot. since we have the actual final list, we can see that Zeus ends up taking that final 13th spot to fight in ragnarok, even though he isnt a combatant in the spinoff tournament.
basically, the spinoff will likely end up being pointless in context to ragnarok proper; its a story for its own sake.