Might require dealing with Chroma Temple to start opening the quest line. These five (the three currently listed, plus two others, if you read between the correct lines) are to be imported as the ... archvillain, so to speak ... of the quest line, and the Guardian Temple quest line is arguably prepping you to face the five.
Now to look for a way to nerf all three a bit while at the same time keeping all three's running gag (collectively, a four-colour pillar + off-group mark; individually from top to bot, player-poison and creature-healing, Graboid/Wings, and HD/Tess).
Also, to figure out how would Nadox fit into the trio. (As for Ion, he's the leader. I almost swear Ion's going to be easier to wing it than Nadox.)0h6s0056u40574j06747037bb057qt068110380g018pn
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21 May edit
I knew it, the element pool is already exhausted for the fourth to slip in.
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As for the bodily stats, I guess 125 HP/3x Mark/2x Draw-n-Deck should do.