I like starting with Treivia because she has Toxicology.
I found Duel with these settings worked best.
Hamlet for the Hardcore+ with Hamlet start achievement.
You want to have high movement speed and Guardposts off and Guards low and that’s really all you need.
Make sure it’s on Hardcore+
Play by Play
You want to unlock guard post first and get as many Minewatch as you can. These guys are really good.
Now you book it to the middle of the map where the Guard is guarding the two halves of the map. You should be able to take him out pretty easily with your Minewatch!
Now you should be at their main base which is usually not guarded by another hero so it should be easy to grab!
After grabbing their Palace, buy some more units for your hero and then go hunt down their hero.