In the World of Sword and Magic as Space Marine

The clash between two fighters began with the sound of a bolter pistol. William drew his pistol with his left hand and began to fire everything he had as he approached the vampire. Meanwhile, Blood Duke stands his ground and uses his magic to shield himself, waiting for the Black Templar to come closer. When William emptied the pistol, he put away the weapon to which he readied the power sword to strike. Blood Duke, seeing the moment, uses the magic of the chaos to match the speed and strength.

With Sword of Pleasure in his hand, Blood Duke swung his blade at William but instead of the power sword hitting back, William dodged the attack using his jet pack to take a short flight. Seeing the knight on-air, Blood Duke was too distracted to realize that William left a Promethium grenade on the ground.

BOOM!

The explosion consumed the vampire and everything around him as William landed safely. Knowing that this fight isn't over, William prepares himself with dual weapons of chain sword in his left hand and power sword in his right. Coming out from the fire, Blood Duke lifts his free hand to gather fire around him which creates a condensed fireball the size of a basketball.

"Now, it is my turn." Blood Duke throws his fireball at William which Black Templar simply charges ahead on, surprising the vampire.

Boom!

A fireball exploded right at William's shoulder armor and engulfed him with a huge fire. Seeing this, Blood Duke slowly approaches the small firestorm to check if his enemy is dead. When the vampire got close enough a giant metal boot came out from the fire, kicking the vampire's chest. Blood Duke flew backward, stunned and landed on the ground with a massive dent in his armor.

Coming out from the fire, William made a quick dash toward the dazed vampire with two powerful melee weapons. The chainsword is the first to strike the vampire as it hits the Blood Duke's right arm, tearing the undead flesh with the sound of a roaring engine. The power sword came next, the blade went through the vampire's armor and pin him to the ground as the entire blade sank to the top of the vampire.

"Checkmate," William said to his enemy as he ready his chainsword but then, he felt a sharp pain from his right hip as if something was stabbing him. Turning his head down, William saw a Sword of Pleasure pierce his armor and slowly bleed out from it.

"If I die, you will come with me." Blood Duke said to William, believing Black Templar will pull back from the duel to save himself. The Sword of Pleasure starts to drain the blood of the Space Marine fast, the pain and blood loss could kill the man in a few seconds. Unfortunately, the anatomy of a Space Marine is very different from regular humans as Space Marine have multiple implants that give him additional organs and give superhuman abilities.

William let go of the power sword and grab the Sword of the Pleasure from the vampire. Before the sword could influence the new wielder, William pulled the sword from his stomach and used his superhuman strength to snap the sword in half, destroying the weapon of the chaos.

"NO! Do you know what you have done?" Vampire protested but it was too late as his pact with his new god was broken. The blessing of the Slaanesh left the Blood Duke's body but with interest as chaos magic drained everything from the vampire. Blood Duke, who sought salvation from his everlasting thirst and pleasure of blood, starts to lose his body mass, skin shrinks and eventually turns into dust.

"This is why you don't make a deal with any of them," William said to himself as he pulled out a first aid kit from his inventory to heal his wound. Thankfully, for some reason, the Sword of Pleasure didn't damage or corrupt William's body. Whether from his purity seal, 'The Champion of the Living' or autonomy of the Space Marine stopped the chaos corruption, William didn't care as he was glad he survived the boss battle.

Just as William finished patching his wounds, he heard the cries of torment from the other side of the wall. Using his jet pack, William stands on the top of the fortress wall to see a bloodbath as the army is barely defending against a small group of demons on the battlefield as one large demon leads them while dancing.

"Kill them in the name of Prince of Pleasure!" Hearing this, the Herald of Slaanesh makes a quick swift attack on the soldiers with their deadly blade hands. Seeing her target, The Masque of Slaanesh dances her way to Prince Benton and Duchess as they are fighting on the frontline.