After Hendrickson recovered from defeat at the hands of Gilthunder through the Black Mark, the Great Holy Knight made his move by destroying the castle, sweeping away all those caught in his attack and awakened the Demon blood of the New Generation Holy Knights causing them to transform into hybrid Demons and rampage throughout the kingdom's capital as the Holy Knights immediately battled their former comrades while he managed to recapture Elizabeth Liones again in exchange for sparing Meliodas' and Gilthunder's lives and proceed to Merlin's old ruined castle to begin the ritual of unsealing the Demon Clan.
While escorting Elizabeth to the underground section of Merlin's old ruined castle, Hendrickson notices that the princess managed to grab hold of a dagger among the scattered items and threatens to commit suicide to foil his plan. Unfazed, Hendrickson was about swiftly grab the weapon from Elizabeth only to see her hand covered by a barrier. Realizing this, Hendrickson and Elizabeth turned around to see Griamore appearing before them with his weapon at his side.
Seeing Griamore alive and well, Hendrickson was pleased that his friend Dreyfus will be happy about this but Griamore declares that he'll stop Hendrickson's sinister plan as he raised a Wall barrier around Elizabeth for protection. The Great Holy Knight swiftly appeared behind Griamore and slashed him with Hellblaze-infused sword, asking the Holy Knight if it's his last words but Griamore easily defended himself from the attack with Wall. Asking Griamore if he's going to stop him alone, Dreyfus, who managed to escape custody for now and retrieved his weapon back, appears and declares that his son is not alone and declares that he'll stop Hendrickson not only as a Holy Knight of the kingdom of Liones but as a friend.
Then, father and son charged in battle against Hendrickson together with the Black Marked-Great Holy Knight ready to face them. Hendrickson was able to keep up with Griamore and Dreyfus, despite being two of them. Hendrickson used Acid Down on Dreyfus, but survived due to his power Break as it make his body never rot or damage which give Dreyfus to chance to leave a giant mark on Hendrickson right side. However, Hendrickson own mark healed itself, but Griamore used Wall once more while Dreyfus was charging up Starstream Breaker Blade to finish off Hendrickson. However, Dreyfus slipped and end up injuring Elizabeth instead.
Horrified of his mistake, Dreyfus runs to Elizabeth's side and orders his son to administer first aid to her wounds immediately. However, Hendrickson easily broke out of Griamore's barrier, having taken advantage of his weakness and swiftly elbowed the Holy Knight in the face, sending him flying. Enraged, Dreyfus declared that it's the end for his friend as the former Great Holy Knight slashed at Hendrickson at great speed but was shocked to see his sword shattered easily as the latter contradicts that it's the end for Dreyfus.
As Hendrickson tells his old friend that he has no chance of winning with no power left in him and admit defeat, Dreyfus responds by punching him in the face twice to no avail while commenting that he didn't want to kill him. Seemingly unharmed by Dreyfus' blows, Hendrickson bids him farewell to his an old friend, mentor and rival as he used Acid Down again on the former Great Holy Knight, seemingly killed him as a wounded Griamore watched helplessly of his father's demise as the corpse begins to rot, leaving only the armor behind.
At the time after Dreyfus was killed, Meliodas and Hawk arrived, took notice of what's left of Dreyfus and a wounded Elizabeth. After taking Elizabeth to safety, Meliodas ordered Hawk to take her somewhere safe and to treat her wounds while he engages Hendrickson in battle where the his fellow Sins Diane, King, Ban, and Gowther joined the battle and prepares to battle the Great Holy Knight together.