Thanks Man, but my friend and me are playing just the two of us, so it's hard to find a good combo to kill all neutral or michael
Grom and Assasin can easily go past bahamut. If you get a bit lucky with drops final disease and Death also arent any problematic. It gets more and more tricky to keep assasin alive though when more splash damage is introduced.Grom with far seer is nice option too though but its extremally drop dependent.
Worker is all in all great support hero. Can keep most of line bosses and creep at the same time with his towers meanwhile other hero creeps neutral bosses.
Thief is kind of good, but bad at the same time :P. You have shittone of money, but if you work with tanky hero (grom, little child abomination) then you lack some true DPS, if you work with high attack hero like assasin or Dante then you lack survivalability, and get rekt by dragons. At least it happens like that for me.
There are more triple/quad hero combinations that work a lot better though.