Can't say I've ever tried it, but you don't know for sure until you do right? So I gave the final one in that last post a try: temkey.
used your little text on it "it's like it's grown accoustomed to the cold... but still likes hotsprings :>" as a basis.
ability:
Flame Body / Ice body (normal abilities)
Regenerator (Hidden)
"When a Maisca spends enough time in a hotspring, their body starts to absorb the heat and they evolve into Temkey. This Pokemon can survive in extremely cold environments thanks to the heat it has stored inside itself prior to evolving. It can control it's temperature at will and commonly attacks it's opponents by latching onto them and either increasing or decreasing it's body temperature to the extreme."
Classification: Temperature Pokemon
