In the World of Sword and Magic as Space Marine

Next Day,

On the first light, the two armies march out of the City of Deron and head towards Fort Stormfist with their two leaders leading them. Meanwhile, giant Black Templar left the city last night to begin his part of the mission.

In the main road, William found the secret path which directed him into a valley with a dead end. Scanning the area, William found the large boulder blocking something so using his superhuman strength and power armor he removed the rock to find a wall with a family crest he saw when he was at Deron.

After pushing the wall with the crest, it revealed the secret passage to the Fort Stormfist. But because his armor prevents him from going in, William unequips his power armor and proceeds to go in with regular clothes and weapons in his hands. Power sword in the right hand and torch in his left, William slowly walks towards darkness as he burns old spider webs and silent his feet to maintain his stealth (As possible Space Marine can).

After 40 minutes of walking in the secret passage, William found himself in the moderately sized room with three different passages. Above each passage, there seems to be a stone carving indicating where it leads to.

'Left leads to the secret door to the treasure room, middle leads to a door to the command center and right leads to back which is next to stables and the supply warehouse.' William recalls the information he learned from Sir Dolven and proceeds to take the middle path to the command center of the Fort Stormfist. By taking the command center, William can freely move around the fort to find the Vampire Lords. When William reaches the end of the path, put his power armor back on and use his helmet sensor to see if there is movement on the other side.

Sensing no movement, William pushes the secret door and finds himself behind a giant curtain of sorts. After moving himself out from the curtain, he found himself in a large room with a large table, multiple chairs and a giant map hanging on the wall (Secret passage was behind the map).

'Ok, it seems like vampires maintain the fort's furniture and other stuff in good shape, I guess they do love life of luxury just like humans do.' William then moves to the door to exit the room but the door suddenly opens from the other side to reveal two surprised humans with metal collars in their necks. William was the first to react in time, he grabbed the two human slaves, pulled them into the room and closed the door. It was quick and sudden because two humans didn't have the chance to make a noise or alert the vampire. William points his power sword towards slaves and asks them a question.

"Do not make any noise or it will be the last thing you will ever do. Now, how many vampires are in the fort and where are they?" William said with a gruff voice which gave an intimidating presence to the slaves who had never seen a giant metal knight before.

"You shouldn't be here, the master was expecting an army for days and brought his entire army to this fort." The oldest looking slave said to William with pleading and warning, which the second slave added with his warning.

"You came here for nothing but death. Your entire army will be master's unless you retreat right now. There is no hope to win, we should know as we were once soldiers to the throne." The second slave warned William but the giant knight didn't budge or gave concerns to the warning.

"Let me guess, he buried half of his forces outside of the wall and hid riders in the forest didn't he?" William said to them which once again surprised the two humans.

"How did you know?" Both men gave a surprised face when William guessed the master's strategy.

"Easy, his vampire lords used the same strategy on the battle of Deron. I guess that your master believes in superior numbers and overwhelming the enemy which is easy to predict the strategy based on that. Now, how many lords did your master bring to the fort?" William asks again which two men answer his question.

"He brought four lords with him, which comprised his entire military forces." The second man said to William but William can see there is missing information from the man.

"There is more isn't it?" The black templar said as he moved his sword from the slaves.

"Yes, since he brought his troops from all over the region, he also brought most fearsome creatures as well. One of them is a master's mount and it is powerful enough to devastate your army by itself." The first man said with fear in his eyes as the second man finished for him.

"He brought a zombie dragon with him. The same dragon he used to conquer this fort and Deron 150 years ago."

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Prince Benton and Duchess marched their troops over the hill as they saw the Fort Stromfist. The fort covered the entire mountain passage from left to right, blocking from passing to the other side. From the left side of the hill, a large forest blocks half of the open field before reaching the range of the fort towers which prevents the invading army from using siege machines.

"Well, cousin. It seems like the vampires were ready for us just like William said." The Duchess said to the prince with a smile on her face. When she heard William's plan it was crazy and stupid as he recommended not to use siege machines. Now, examining the battlefield, she can see the open field covered with fresh dirt and no overgrown grass, which supports William's advice on the buried undead army.

"Just like the battle of Deron, vampires plant their undead underground for an ambush. This also means they hid shock cavalry somewhere, possibly in the forest right over there." Prince Benton points at the dense forest. Suddenly, officers from Prince Benton's order the troops to make formation with a tower shield, creating a big wall of tower shields with swordsmen and riflemen right behind them. The Duchess and her troops saw all this with amazement as they didn't expect the prince's troops to be well organized and disciplined. It was as if they were looking at experienced veterans on the battlefield instead of spoiled minor nobles' sons and lazy army with expensive war gear.

"All troops! Forward march!" Prince gave his order which entire wall of shields and troops behind them marched simultaneously. When the army reaches a certain point in the field, the undead starts to rise from the ground, preparing to kill the living. Unfortunately for the undead army, a wall of tower shields open gaps between and a volley of rifle fire shreds them before they could reach the living.

As undead troops get wiped out from the field before they could do anything, the vampire's shock cavalry reveal themself out of the forest with a sound of heavy hooves. The cavalry is composed of 400 Crypt Knights with heavy armor and 80 undead war dogs with light armor. In normal circumstances, it will take an entire wall of spearmen or company of crossbows to repel them, but Prince and William brought something new to this fight.

"Riders are approaching! Bring out the big guns!" one of the prince's officers calls out as soldiers in the rear bring out four wagons with something attached to it. The metal mounts on the wagons are made out of rifle-like barrels but much bigger and hold 8 rounds each. There are 16 individual barrels divided into four decks, making it rotatable after each deck fires the round. It is a fantasy world version of a Gatling gun and similar to Helblaster Volley Cannon from Warhammer fantasy Check (Total War Warhammer 2 for reference).

"Fire the Volley Cannons!" The second prince gave his command, the four wagons with Volley Cannon fired, destroying the first and second lines of undead knights and war dogs in one set of a volley. The rounds from each cannon pierced Crypt Knight's armor like it was made out of paper. The cannons continue their fire as they rotate to cool their barrels, by the end of the fifth volley, most of the knights fell and war dogs are no more.

"That was much more effective than I thought. Good thing that we spend two weeks wisely by building these artillery weapons." Prince Benton said while the Duchess and everyone around her saw all this with their mouth opened.

"Who exactly are you, Sir William?" The Duchess said to herself as she and the rest of the troops slowly followed the prince's army.