[Kyrvias]

Revenants can eb tricky- you need to watch how much aggro your casters generate, because that undead has a tendency to target them, use their pull ability, then take them out.

Using obstacles helps immeasurably- interposing a column, or bookshelf, or gravestone between casters and the revenant is preferable.

Generally, take out the minions first, I'm assuming skeletal archers and swordsmen in this case. They drop faster and, if you can keep your tank(s) healed, they can last long enough to then fight the revenant directly.

Long and short: The revenant is vulnerable (and able to be taken down) alone, but with minions, you just won't be able to keep up with the damage they're putting out without losing characters.