Ulduar is a raid instance in the popular MMORPG World of Warcraft, introduced in the Wrath of the Lich King expansion. It is set in a massive titan facility located in the Storm Peaks region of the game. Players explore this ancient structure, which is filled with powerful enemies and intricate puzzles, while uncovering the lore of the titans and their creations. The raid features several notable bosses, including Yogg-Saron, a powerful Old God, and General Vezax. Ulduar is known for its unique mechanics and the option for players to complete encounters on different difficulty levels, making it a memorable experience for both casual and hardcore players.