To explain the full event....
The event takes place in a ring near the bridge to Netherstorm. There are five small circles of fire around the edge of the ring.
When characters stand in the circles, red lines form between them. So, each occupied circle is linked by a red line to the other occupied circles. When all five circles are filled, the red lines form a pentagram, and Vim'gol, an ogre warlock, is summoned.
Vim'gol will pause for a couple seconds and complain, during which time he is invulnerable. He will then attack whoever was the last character to step into a circle.
He attacks with a heavy melee hit and a Shadow Bolt Volley that hits everyone nearby. A tank, a healer, and some solid damage-dealers are highly recommended for this encounter.
At 50% health, Vim'gol announces that he's going to grow large and smash everything. He then runs to the center of the ring and channels a "growth" spell for 10 seconds. If five characters get in their circles and re-form the pentagram, it will interrupt his cast, and he will not grow. If it completes, he will be very large, dish out substantially more damage, and likely wipe the attempt.
When he dies, a container appears at his feet. Loot it for the quest item.
Some tips:
Have your tank enter the fire last. That way, he'll head directly for the tank.
Healers, ranged damage-dealers, and the tank should not move until the the growth spell is dispelled. If all five characters simply stay in their circles after the event starts, the growth will never happen. Only melee damage -dealers need to run around.
Everyone will be taking damage. Use potions and bandages to relieve pressure on the healer. Five living characters are required to stop the growth buff, so make sure you're alive at least that long.
The quest item container appears to be lootable by anyone with the quest. There is no need to be in on the kill or the summon.
Since it's an outdoor event, characters outside the group can assist with healing and damage-dealing, to break the five-man group size and make the event considerably easier.
Despite the experience of some well-geared players who have commented here, it's considerably easier to finish this event if he does not get his growth buff. Do run to the circles.
Make sure that you are not standing in the circles of fire when Vim'gol dies! If you are, he will be instantly summoned again, and at full health! You can still loot his quest item if this happens, though.
TheWoWDB
