The legendary damage for your attack is a good choice as the frontlines are for most slow moving and thus you can deal insane damage while counter their damage with you illusions (you can also use them to disrupt the beam of torvald)

When you face lex, try to stay at range as you can deal morde damage to him from range, if you're a skilled player and keep rolling, you may have the upper hand on him, also knock him back prenvents him from escaping and impact his aim.

The lifesteal is often the thing that will prevent you from killing her, with cauterise, it's still a bad match up but your odds are greatly improved.

When facing torvald use your turrets as decoy and get out of range of his beam, try to bring him to your damage dealer and keep spawning turrets to heals and disrupt his attack