The launch of Warlords of Draenor was marred by server issues, the presence of choke points, and a denial of service attack.

The World of Warcraft expansion went live Thursday, but millions of players all attempting to log on and complete the same quests at the same time saw things slow to a crawl for some players.

An early quest giver and quest tool were mobbed by players.

The expansion’s congestion problems were multiplied when a DDoS attack dramatically increased the game’s server load.

Blizzard issued a number of hotfixes and later took the servers down for six hours of maintenance.

“We’re excited to finally launch Warlords of Draenor and explore this new world with you, but we know that the experience has been less than ideal as we approach our first full day of launch,” wrote community manager Micah Whipple on Battle.net.

“Thank you for your zeal to face down the tyranny of the Iron Horde – and for your continued patience as we work to improve the current experience.”

Things appear to have improved since, although queues remain an issue for some.

"With many of the new changes that have been implemented over the past couple of days, we’ve seen a marked improvement in realm performance and stability," wrote Whipple yesterday.

"Thank you again to everyone for your patience while we have worked around the clock to address these issues."