Late-game Revenant is unkillable beast.
With right play-style u will get 0% damage.

Usage:
2nd ability for Mesmer skin, with active Mesmer skin u will be imune to any damage. [Rolling Guard] makes u invulnerable while u are recasting the ability.
1st ability to controll enemy and makes him inflict others. While they are inflicted, your 3rd ability basicaly oneshot them.
4th ability swap with Roar. Bonus damage 101% for every damage output as a faction damage.

And thats pretty it. This build is simple as it can be. So enjoy. :)