Currently working my way through the Circle tower - taken Alistair, Wynne and Morrigan with me (Wynne is REALLY useful with her heal spells). Just on 2nd level, found a statue turned over; looked at it found a vial, opened it - EEK a Revenant!!!.
Killed it, just used mainly hex spells to make it more vulnerable to ice/fire etc.
Still it was tough, hope I don't face more than one later on
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Once I done the tower, might go next to Sulcher's pass, then its back home to Orzammar to see whats happened since been exiled.