World Tree

«Yggdrasil» is the tree that is at the center of ALfheim Online. The tribe which reaches the legendary city floating above Yggdrasil and has an audience with the Fairy King Oberon who lives there is able to be reborn into true fairies, the ALF. The hover limit imposed on the system will be eliminated and unlimited flight is possible. Along with it they are capable of becoming rulers of this infinite sky. It's possible to enter this floating city through a dome at the root of Yggdrasil. However, guardian knights who boast of overwhelming strength guard the entrance, one year has passed since the opening of ALO, yet this quest has not yet been cleared.

ALfheim Online
Kirito climbs up to the top to rescue the captive Asuna from Fairy King Oberon.