Tower of God Manhwa Volume 4 features story and art by S.I.U.

Twenty-Fifth Bam must journey skyward in a mysterious tower if he has any chance of reuniting with his best friend Rachel, even if that means facing his own death. Using his strength, skill and wits, Bam climbs higher and higher up the Tower despite the dangers. Bam makes both allies and enemies on his quest to find Rachel; however her intention to reconnect with him becomes unclear as new revelations about their friendship reveal a much deeper, darker secret.

The surviving Regulars are preparing for their next major test, and Bam is making shockingly fast progress in training. While Khun and Bam are focused on forging new alliances and friendships, Anaak and Rachel keep quiet about their big secrets. And now the fractured group will have to join new teams to take on their most dangerous opponent yet: someone who has already made it to the top of the Tower.