I'd say Mabrigitte, or if I was locked to your choices Zamboni.
How noble of you - to blindly kill without question, to come for my head on the barest word of another. Sheathe your fury and hear my tale first. You'll see what noble ignorance has done to these lands.
Zamboni works on several levels.
Hidden Option 4: Mazula
"It is arrogant for one to reject change because it is undesirable. Rejection of change is the rejection of possibilities."
— Harald Hoerwick —
• Zamboni sounds like a troll name in the actual lore. +1
• Zamboni can be considered an ice/frost reference, which relates to Death Knights. +1
• Zamboni also sounds like a massive truck and/or a mob boss that will demolish/steamroll you. +2 for badassery.
Where's the xXDéàthknightXx option? Voting for Zamboni, seems the most fitting.
One more vote for Zamboni for all the previously listed reasons.