Tsubasa: Reservoir Chronicle, Volume I-III — CLAMP

In Volumes 1, 2 and 3 of Tsubasa, Sakura and Syaoran face their greatest challenges in alternate realities where whatever you least expect can happen-
and does! Sakura travels to the archeological dig that is being led by Syaoran to declare her love for her childhood friend. But the discovery of a puzzling symbol sets events into motion that lead to Sakura losing her memory, Syaoran dealing with a witch to save his beloved, and both traveling to a new universe to face a frighteningly powerful magician. Now, Syaoran and his new traveling companions, Kurogane and Fai, must travel the worlds to save Sakura's soul!