well its hp will jack up 1k so it'll be very much more useable later imo. But yeah, sub material, not starter if that's what you're asking. And you mean light descend dungeons don't you? it prevents light damage, not dark. Anyway, once they get their hp, they will be a good substitute for an ecchi-nida provided you have the appropriate colour, better in the cases of bosses that attack every 2 turns, or 4+ (equal if 1 or 3).