[Sombre]

Void touched ichtyids who have been forced from their coastal homes by the more advanced land nations are a possibility. Oceania could be a sort of refugee nation sandwiched between the land and ryleh. I mean since the atlantians have moved north and the shamblers are all but wiped out,... I'm thinking the lighter skinned coastal atlantians could be on board with Oceania too. That way you have a triton based sea nation that's all about smacking ryleh around, but with 'marines' made up of ichtyids, atlantians and mermen specifically armed to storm the beaches. Up on the surface world the big new thing is high tech heavy armour, so it might make sense for them to have armour negating or piercing weapons coupled with entangling/netting stuff.