It all comes down to your damage output. If you haven't put effort into party selection and just run with randoms you're going to struggle. You'd either have to reroll or settle for a 10 minute fight. If you have a strong aresenal of ranged dps then shoot-run-shoot-run. You could also try having a single tank so he's less likely to hit 6 characters with his healing attack, and only hits 1. In elite he's 0 struggle. No running, no changing characters, no sweat. Just have a look at the group build I posted.
Agaroth - 100 Warrior in DeletedLand
Grigori - 100 Warrior farms Calennor
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