"Immortality" Implant

[Roomba]

There was a brief period a while back when changelings had a limited form of "immortality": they couldn't die from brute or burn damage no matter how much of it they took, and had to be outright gibbed or had their brains cut out in order to kill them.

It sucked and was removed for pretty much the reasons mentioned earlier - new players didn't know how to counter it and quickly gave up on even attempting to fight changelings, while it was barely a speedbump to experienced players.