In short, two minerals still need a use beyond the prestige missions. A logical solution would be to create 2 more battle sprites to feed on these. My recommendation? Jelly Ants! It fit thematically in my head and that's what I'm sticking with. That also leaves room for one other option if this one was selected.
This thread belongs in the suggestions subforum.
And there should be more details if you are trying to suggest a battle sprite.