[NecroBlade]

Mostly agree with @Captain Stupendous .

B: I think part of what some are struggling with for this option is the term "mutant" has been thrown around too loosely. She would not be a mutant in the same way Motley Max is, and in fact I don't think she'd be a mutant at all (though I will point out again that even if she were, the two types - genetic and nuclear wasteland - are not mutually exclusive). The Earth 2210 timeline from RISK that already has a bunch of Heroscape connections (namely Microcorp Agents/Troopers), plus the Motely Max 2220 connection, includes genetic research and the underwater city New Atlantis. Durnipia* is a perfect fit for an altered future human from this setting. And yes I have the mini in hand: she's a blue humanoid with fins, this is not a stretch. Her garb has been brought into question, but it also seems fitting to me: it's gold and has a scale/shell look to it that fits the Atlantean trope. The New Atlanteans are reclaiming their long lost heritage, including the look and the technology (sort of a la Assassin's Creed) recovered from the ocean: her bident which allows her to manipulate water/liquids, moving and healing allies and making attacks. Bringing it back around to my earlier point: her species would be [New] Atlantean, not mutant.

*It's worth reiterating that we only know 2 sentences about Durnipia, neither of which would preclude us from using the name for any of these options.
From Valguard: "It was on Valhalla that Valguard had the alien lizard arm magically attached by Durnipia, to replace his lost arm."
I'll quote Thor for this one: "Your ancestors called it magic, but you call it science. I come from a land where they are one and the same." That is to say, for the inhabitants of Valhalla technology that is alien to their world is indistinguishable from some kind of magic.
From the 10th: "Madam Durnipia has healed many from grievous wound that surely should have killed them."
All that tells us is she's a healer. It is a little disappointing that Healing Waters doesn't currently do anything for Squad figures. That could be retooled to wound prevention, but mechanically and meta-game wise it may make sense to keep it limited to heroes. And we all know the bios don't translate perfectly to game mechanics [looking at you, Khosumet].)

A: This is palatable if unexciting. Feylund is vastly preferable to Toril for a couple reasons: this isn't a D&D set so a one-off D&D character feels really out of place, and it was a mistake to include D&D in the Heroscape canon in the first place since it's a game played on Earth... which exists in the same canon.

D: Arctorus is a bit muddled and I don't see a concrete place for her there.

C: There are four distinct species at war on Marr with full factions. I don't think adding a one-off fish lady does us any favors.