Ichigo is losing his battle against Yhwach and he needs some reinforcement more than ever. In the next chapter, it is believed that Isshin, Ryuken and Aizen will come to his aid.
Upon Ichigo's unveiling of his Bankai, Yhwach immediately destroyed the sword just a few seconds after by using his time manipulation ability. Hence, this led fans over at Manga Helpers to speculate that someone will intervene in their match and assist the protagonist for the time being. His father, Isshin, is expected to arrive first along with Uryuu's, Ryuken.
Both will show their respective powers and will be able to go toe-to-toe with Yhwach. However, they will not be sufficient to defeat the Almighty ruler. This will lead to another iconic figure to appear and help their cause.
Currently stuck in a chair that caps his Reiatsu, Aizen is expected to have found a way to break free from it. Later, it will be revealed that he has made his way to the top of Soul Society, leading to Yhwach's palace. Fans also discussed what his motivation for helping Ichigo would be. Some believe he will want to be the one to slay Ichigo and get his revenge after getting defeated in Hueco Mundo.
Some believe Aizen will be assisting the Shinagamis as he hates the idea of someone other than him will be conquering the Soul Society. Lastly, some think that Aizen will find him as the greatest challenge so far and defeating him would mean he can finally outmatch Ichigo in a battle.
Meanwhile, fans over at Reddit think Aizen would not be able to do anything against Yhwach alone, which would force him to team-up with Ichigo. Together, they will find a way how to stop the leader of the Sternritter from transforming the future, and this will also lead to Ichigo getting his Bankai back.
As a quick refresher of "Bleach chapter 679, Ichigo was about to make a powerful attack using his Bankai, only to be halted by Yhwach in an instant. The former then made his counterattack, leaving Ichigo helpless. Here is a recap of the previous chapter.