Loki is a way harder nemesis to deal with than any of the others. The chance for him to heal with the random mechanic means you really only want to defeat him when you know what is coming or you have no other option and have to hope. Otherwise you are wasting actions and damage unless you get lucky.
Attack: 2. Scheme: 2. Health: 4.
Interrupt: When Loki would be defeated, discard the top card of the encounter deck. If that card is a treachery, heal all damage from Loki instead.
(Thor's nemesis minion.)
"You seem disappointed, brother. That's good."
Thor #28. Thor Nemesis #2.