No seriously, why did you think giving an ability for pandorans to respawn the next turn and immediately have 4 action points an engaging way to play the game? There’s also the issue that this interaction is bugged and alot of the times it does not render that the Arthron is resurrecting itself properly.
From a gameplay perspective, this completely kills melee and shotgun builds. A hatching Arthron where you can’t disable essentially is death for anyone who is within 1 AP move of the creature. It’s stupid.
From a lore perspective, how did the Pandorans even get ancient technology? The whole LotA expansion was supposed to be about phoenix pursuing an area of research nobody else was aware about. If the Pandorans take over one of my gas fields or ore mines, fine, but currently why even bother attacking my ancient sites if they can just evolve out of thin air plentiful supplies of Protean gas and Orichalcum?
From a mechanics perspective, if mind control disables you for a turn, why is reassembling your body from a bunch of ancient gas completely instantaneous?