That was quite a snoozer of a survey dungeon, but in retrospect it’s actually one of the more useful ones in a long time since it gives access to an actual monster and not just its skill up fodder. Kamui and all the Mystic Knights aren’t very impressive, but all farmable orb changers have value. Kamui is particularly good since he combos with both Karin and Skuld; he doesn’t even come close to Trunks in that regard, but NA has to make due with what it has. Now that he has reasonable skill ups, he should be seeing a lot more play on water teams. I strongly recommend that you skill one up if water is your main element.