--- Note: This mob is affected by 'A Dark Cold Shard' - a possible loot drop of the Shade of Miragul in Scion of Ice ---
Kervis has a odd way of starting his encounter. You will actually pop Kervis with a ranged attack and he will send one his guards out instead. Kervis will reset inside his room at this time. Kill the first guard. Hit Kervis again with a small ranged attack and he will send out his second guard.
The next time you hit Kervis he will come to the raid. Kervis has 3 AOE's (however one AOE will be removed if you used a Dark Cold Shard when you zoned in) One Trauma and Two Elemental AOE's. The trauma will be removed by the shard. The AOE's dont hit that hard if your raid jousts them or stays 15 meters away and jousts in when the Trauma AOE hits.
This fight is a simple tank and spank. Kill his weak adds that come with him and he will be a quick kill.