https://pobb.in/KbiMwsKLiOZ_

This is a very quick tree to try and maximise polymath. It may not be the best, assassin might still be a better option, I just wanted to see how far I could go if I stretched. The answer I got was 15 masteries.

It's very possible that the correct route would be to use clusters instead of pathing to the scion ES wheel, I just didn't want to mess around with clusters quite yet.

The end result of this tree is a very tanky character, with decent ES, decent evasion, and great spell supression (don't forget, the small nodes on trickster also give ES and evasion).

Also, as a side note- the +2 frenzy charge node would be really nice with affliction charges for this build.