Skip ahead a bit (about 40:15). The first version of the deck in this was flawed. The last version is too, but much less so, and is much more reliable.

A 3/60 with Ranged, and when he deals damage to something, he deals damage to every adjacent enemy as well ("enemy" being you), but also he receives all damage he deals. Starts with a Golem Vanquisher (2/4 all Golems get Provoke) in the middle of the board.

Have a limited collection? Watch the budget version here:
http://www.dailymotion.com/video/x5nmuvi_duelyst-boss-battle-11-budget-automaton-8_videogames