Zeus? I mean Skadi also followed this pattern of Anniversary after the Lostbelt. Not sure why Lolinardo was between them though. Could be the reason DW tried so hard to bait with the Summer crapsack banner.
There’s a lot that makes sense, Zeus is one, there caster limbo and captain nemo as well. People said that recent FGO events are screwed due to the postpone of Olympic Games. I wish they could pick up their work with anniversary gifts and summer 5.
Oh yeah forgot about Capt Nemo. Not sure about Limbo though. He was established as this lurking antagonist that’s waiting for you somewhere and people have been speculating that the next LB is between LB5 and LB6 where we face him. Doesn’t seem likely that he will be summonable before his arc is finished.
Anni 5 is kinda big deal, so my bet and already established fan-desired character: either Koyanskaya/Vitch or Muramasa (as OG Shiro pseudo-Srvant).
Galahad is also possibility… but, I think, DW is saving him for LB6