The Fearsome Pursuer「恐るべき追跡者Osorubeki Tsuiseki-sha」 is the 8th episode of The Seven Deadly Sins anime series.
The mysterious Holy Knight, is revealed to be Guila, who threatens the kids and succeeds in gaining entry to the Capital of the Dead. Meanwhile, inside the Capital of the Dead, King petrifies Ban in an act of revenge for his sister, Elaine. However the spirit of Elaine chooses to reverse the petrification, much to the surprise of King. Here, Ban and Elaine's pasts are explored.
Whilst looking for Ban and King, the two now split from the rest of the group to chase after Elaine, Meliodas and the others have a run-in with Guila. The battle begins between Meliodas and Diane fighting against Guila, however tremors from the battle with Guila reach where Ban and King are, forcing Ban to join the fight against Guila. Left alone with his sister now, King listens to her plea to help Ban, and switches sides. With that done, King leaves to help out the other Sins, who are still struggling (even with the arrival of Ban) in defeating Guila.