Event period: 3 weeks (12/10/14-12/31/14) Event style: Limited cooperative Event objective: Take down event boss Event rewards (first kill): Limited edition title, profile campaign medal (?) Event rewards (subsequent kills): Gold, mithril, etc...
Event items: Snowballs (common mob drop), coal (quest reward) Snowballs - Deal 1 damage to event boss, uses 1 from inventory Coal - Event boss regeneration does not trigger for 1 second (not cumulative)
Boss: Abominable Snowman HP: 20000 HP regeneration: 10/second
Strategies: Brute force - Power through with bodies alone. Collect enough snowballs to account for the regeneration of the boss while fighting. The grind is slow, but it takes at least 10 people (assuming 6 second auto, so 10 attacks per minute per player) on auto to break even or advance. This method is harder because of snowball collection time, coordination, and lack of coal.
Layered - Split the group into smaller groups with rotating coal into the attack pattern. Each player has a higher workload, but the attack should take less time, people, and give steady indication of the spawn trajectory. Planning may take up more time because the rotations require the coal to continuously pour in. A single piece of coal essentially does 10 damage, but not without existing damage to the boss.
Mixed (Casual) - The most likely outcome is an attack combining the above in improvisation. The refinement is less than layered, but easy to plan like a brute force attack. The sheer numbers will make the success of this plan likely.
Event evaluation: Reality is all group sizes and skill levels have a place in the above scenario. Coal is the domain of newer players and grinders. Higher level members will plan attacks and provide the bulk of the snowball efforts. The above strategies outline small and large groups (as well as everything in between) succeeding. Custom titles or medals give something unique to remember the event by without changing the dynamic of the usual quest reward.