Lord of the Rings Online: Siege of Mirkwood?
As part of the Turbine Tuesdays sales, the LotRO store will be selling the game's second expansion for half off the regular price this Tuesday, December 28th. Siege of Mirkwood is priced at 995 Turbine Points in the NA store (which is around $10), but on the 28th the cost will be halved to 498 ($5).
The Siege of Mirkwood expansion unlocks over 150 quests, zone deeds, five instances and plenty of content for high-level players. Currently, free players may access the zone and experience the epic storyline, but the rest of the content is walled off unless this quest pack is purchased.