My ideias are:
Equip cards, second set
The addition of a second set for card slot. Changing between then for certain situations, but can only swap sets in cities and maps, not in dungeons or pvp. Can be even sell it for tp (the second set)
Card for fire builds
If Ice builds have a card to support them (Hydra that boost damage on frozen targets) so Fire builds need a card like that too.
Nebulas
We need Nebulas as a card for we to summon plz ^^
Or, at least, take inspiration from her to make a new class maybe.
