Concluding that all of the Seven Deadly Sins will be deployed to retake Edinburgh Castle and take out the Vampire Clan including Escanor, the one that King, Dreyfus and Hendrickson were unnerved of, Ban was sent in first for enemy reconnaissance by Merlin.
Arriving at the Edinburgh Castle, Ban in full armor finds a recon mission assigned to him by Merlin to be such a pain but was grateful enough that he didn't get to taste Meliodas' disgusting meat pie he cooked after winning the card game that the loser treats the winner to a meal while boldly walking into the castle wondering if there are any good treasures around.
The Fox's Sin of Greed's presence was noticed by the members of the Vampire Clan within the castle who at first believed him to be one of Edinburgh's Holy Knights who managed to escape the vampiric conversion or massacre before realizing he came from another kingdom. Sooner than expected, Ban encountered all of the vampire Holy Knights of Edinburgh about to gang up on him in great numbers, intending to rip him to shreds or turn him into one of them but the Fox's Sin of Greed quickly decapitated them all with his Snatch's Assault Hunt and Sacred Treasure nun-chunks, killing them with their heads flying much to the Vampire Clan members' surprise of his strength and decides to eliminate him as they now perceived him as a threat with Orlondi volunteering to drink Ban's blood.
After killing the last vampiric Edinburgh Holy Knight easily, Ban was a little displeased of the vampires' performance in battle and wanted a better challenge before suddenly being dragged into the castle forcefully and confronted the member of the Vampire Clan, intending to drink his blood.