Tower of God

It is said that if you manage to climb to the top of the Tower of God, any wish will be granted. Rachel can't bear to live in darkness anymore and so, despite her friend Bam's wishes, she opens the door to the Tower to begin her ascent. Bam, in despair, follows her, only to learn that ascending the Tower isn't as easy as just walking up stairs. A strange creature named Headon tells him that he will have to pass tests to prove his worth, the first of which is evading a steel eel and breaking a black orb. Aided by Princess Yuri of Jahad and her companion Evan, Bam gains the magic sword Black March and is able to move on to the second floor. Rachel can't be all that far ahead – but it may cost him to pursue her.

Synopsis from Anime News Network