NHF – new heroes for Heroes V 3.1.

You can give Sanctuary heroes to someone else (maybe they ran away from the Naga or something similar).
Or you can make a Sea Elf hero for the Elves (I don't know, but maybe you already have one – I don't want to read the whole thread).

Actually, I had an idea to create a Sea Elf hero for the Elves with a special ability that summons Hai Ro (/topic/at/442362/) – the mechanic would be like this: instead of a non-functional Yeti, a sacred Kirin from the Naga mod is placed; then, an Avatar of Death is taken and edited so that its special ability summons exactly this creature, not one from Necropolis. But as far as I understand, we cannot clone a special ability and edit the clone – meaning if we edit the Avatar, Arantir will also summon not a spectral dragon at all.

By the way, could you please tell me what unit #90 is (is it perhaps a Yeti?)