Yep Mael's Cruel Sun. Also here's FKS' summary on the chapter.
- Mael never expected to meet someone who was once his enemy. He supposes this is the fate brought by his grace. Escanor recognizes him as Estarossa… no, as Mael.
- Diane notes how badly beaten up he is, and he apologizes for being useless and embarrassing. Elizaeth heals him.
- Mael says Escanor got blown away and got caught by him, adding King saw it all. The Fairy notes that Camelot's in a miserable state.
- Escanor recalls Merlin and the cocoon, and tells Mael he heard from his brother about his Sunshine being the grace.
- He wants to return the grace to him. Mael however says he can't accept it as he was ainted in darkness, causing it to ignore him and choose Escanor as its host after ages. He adds he has no right to host it.
- Escanor tells him he doesn't have enough lifespan to withstand Sunshine, that without it, victory over Demons is not possible. He adds they have little time, that if it isn't done quickly, the point of no return will be reached. He then says if Mael doesn't ant to accept it, Escanor will lend it to him. He tells him to protect the people he holds dear.
- The fight between Ludociel and the sinner continues, and Merlin needs ten more minutes to complete the spell and hopes Meliodas doesn't wake up.
- Ludociel uses Lightning Spree, which roasts the Demon quite a bit. Hendrickson notes that he managed to injury the beasts where Escanor couldn't.
- The sinner then uses Hellblaze Omega, which Ludociel bloww up. The Archangel then uses Sparking Drive on him. Another Helllaze Omega from the sinner, which somehow works this time. Ludociel notes that the technique's power rose, and proceeds to wipe the Demon's smile off his face.
- A third Hellblaze Omega which blows Ludociel, knocking Merlin over.
- The Archangel finds it odd as the Demon's damages should have accumulated, yet his magic output increases. He then notices something about the sinner: the Original Demon is actually decaying, it isn't due to the damages he took. Merlin says another of his attacks will be very dangerous.
- The sinner says the more his life gets eroded, the more powerful his power gets. He calls it Crisis.
- He then says he'll gladly give his life if it's for the birth of the new Demon King.
- A ray of light pierces the clouds that the Sinner created. It is Mael's doing. That's right, he arrived at Camelot, and it isn't just him.
- Zeldris smiles about the return of Estarossa, no, of Mael. The Archangel is seen holding a rather big sun.
Title of next chapter: Mael vs. Zeldris.