'Hmmmmmmm...' Between thumb and forefinger, Avan stroked his chin and the beard, which had grown several centimeters long by now.
After defeating the descendant of Xavier, the rest of the march through the gorge had been relatively easy, especially since there were almost no ghouls left to ambush him. The descendant had rounded up almost all the raging ghouls in his ambush, reducing the population of the beasts to almost zero.
With his newfound skills, or knowledge, Avan had had no trouble climbing out the other side to the north, crawling and sneaking through the knee-high grass thanks to the approaching "night" in the cave, which ended in a simple dimming of the glowing crystals on the ceiling.
And now stood pressed against the outer wall at the bottom of the fortress, while he tried to spot the patrols at the top of the wall along with the patrol times. 
'I don't know what level the guards are. If they are also elite guards, it looks very difficult to take them out unnoticed. If I even have to deal with just one. Even if they are normal guards - it will be noticed sooner or later if they are missing. So also a stupid idea. Sneaking through? Maybe, if possible.' He thought hard, trying not to make any noises like he usually did. 'I simply know too little to risk discovery now. If I need more time to get the others out, or there are more prisoners, or something else happens, then surprise must still be on my side.'
He faced the problem of having too much ignorance of the situation ahead. No matter how he twisted or turned it, sneaking in was more difficult, but would bear the most fruit in the end.
Nodding slowly and agreeing with the plan, Avan slowly turned to the wall and gently placed the claws of his right glove into the masonry. Minimally and only very softly crunching as the pointed celestial claws penetrated, he began contentedly and quietly climbing upward, hand by hand, and one foot at a time.
Thinking that perhaps the vampires had very good hearing and equally excellent vision, Avan took his time, preferring to make his way carefully and as silently as possible to his destination; the battlements above him.
The twenty meter high wall took his time to climb, and as Avan hung in the last meter to just before the battlements, he stopped with bated breath as a soft clacking sounded in the distance, slowly approaching. Arms trembling slightly as holding still in the same position as muscles and tendons cramped uncomfortably, he waited until the guard approached from the left and marched on to the right, seemingly alone but on the way to a second guard waiting in the angular tower a few meters away, which Avan could see out of the corner of his eye thanks to the torchlight.

Very slowly, Avan's breath rose in little clouds between his lips, because even the air had cooled down considerably more in the artificial "night" down here, and he ducked up between two battlements to immediately throw himself onto the floor of the walkway and listen eagerly for any alarm cries to reach his ears.
After a few seconds, when nothing unusual was shouted or any alarm bells rung, and the two guards on the watchtower to his right only talked casually to each other without looking in his direction, Avan crawled on, crouched and almost crawling in the shadow of the walls, until he stopped at a wooden railing leading down into the courtyard.
A small wooden staircase, one man wide, led down and he could see the courtyard in its entirety for the first time.
Leaning against the outer and inner walls were stone dwellings, with simple wooden blinds and wooden doors, a fountain further to the left in the courtyard between the houses, and various typically dark and gloomy stone carvings adorning the huts. The fountain itself was adorned by a statue, similar to a gargoyle, which sprayed water into the air with its open mouth and between its well-crafted jagged teeth and the water landed gently in the pool surrounding it.

'Pretty...' It went through his head, and the same turned further to the right to examine the front part of the courtyard between the two walls and what lay further to the right of it.
Various wooden apparatuses, workbenches, forge ovens and also smaller market stalls greeted Avan in the front area, while much further to the right in the fortress the metal cages caught his eye from afar, which left only fist-sized squares free with barred metal bars all around and a locked metal door on one side.
Four such five by five meter cages stood there, and further up on the battlements inside and outside one could still see the glimmering of further one-man cages to starve out prisoners.
Out of the corner of his eye, Avan saw that the two guards in the torchlight had just finished talking, and that the other guard, who had been waiting there before, was now making his way in his direction, seemingly in constant rotation with the patrol of both guards.
Quickly, yet slowly, Avan felt his way down the wooden railing and the stairs, careful to stay as close as possible to the wall and the shadows, while carefully scanning each step to see if it would creak and squeak dangerously under his weight.
Just as he had reached the central corridor of the stairs, which made a right turn there, he quickly pressed his back against the wall and remained breathlessly in place. The guard, perhaps because they always did it or because it had heard something, had just at that moment glanced from the battlements to the stairs and let its red gaze glide over Avan with his hood up and the stairs.

Avan did not dare to make even the slightest movement while he looked straight ahead at the inner fort to show the searching guard only his side view, which, with the midnight black robe and hood, completely hid him.
Only after he could hear the footsteps behind him on top of the wall again, and they moved away to the left, did he dare to exhale and calm his heartbeat and breath. 'Ohkaaay, that was a close one.'
Waiting a few more seconds to calm down and not accidentally making a noise that could have been avoided as the adrenaline quivered, he continued down the last set of stairs that ended directly on the hardened earth of the courtyard.

Creeping from shadow to shadow, crack to crack, and dodging the inner guards, some time later Avan had reached the right part of the fortress, and was lying flat on one of the stone dwellings, which was probably fortunately used as a store or workroom, and he would hopefully not wake anyone below him with his climbing.
The message, which he had not seen for a really long time, he pushed aside for now, nevertheless happy to see visible progress once again.

Passive ability [Sneak] obtained!
Thanks to your inflitration into a castle full of probably hostile and bloodthirsty vampires, your constant almost peeing your pants, and your courageous ambition, you have earned this ability.
Gives you the ability to get from one place to another unnoticed, as long as you keep a low profile and stay undercover.

With a grin between his cheeks, and glad to have the snarkiness of his system back, Avan refocused on the cages in front of him and let his gaze wander over the occupants.
Almost exclusively women and children of both sexes were to be seen, while armor, clothing and weapons of all kinds, presumably belonging to current or former prisoners, were stacked relatively neatly in a few piles on the right side of the wall.
The four cages were each guarded by two patrols consisting of two guards, who marched around the cages constantly but whispering to each other, every now and then making remarks or gestures in the direction of the prisoners, and chatting briefly with each other when they met. A laugh drew Avan towards the two guards who were currently marching along the wall near the looted items, and one of whom was thrusting his spear through the bars to poke a young mother and her two sons, causing a panicked and terrified scream, and the two laughingly continued on their way.
'I guess sleeping is out... poor sods.'

Shaking his head and feeling sorry for the situation, but unable to change it, Avan looked further and finally found a part of his team in the left cage, sitting in the middle of the cage in rough and simple clothes and giving evil looks to the laughing guards passing by.
But what made him frown and immediately noticed was the absence of two people; Linob and Patris! And since Avan could clearly see that there were mainly children and women, he knew immediately that the men were being held somewhere else or that something was happening to them that required immediate haste.
With quick and hasty glances, he looked around the courtyard, trying to figure out where they might have taken the men, and where he would find Linob and Patris. His sphere of influence showed him that the house below contained only wooden workbenches and odd devices that looked an awful lot like torture tables and belts, but also housed no men.
'Maybe the houses further back?' He guessed, since the houses on the left only housed the vampire inhabitants in odd sarcophagi or often soft beds, while he had yet to explore the keep in the middle and the houses in front of him.
He waited for just the right moment when all four guards met and briefly laughed with each other, probably making fun of their antics with the prisoners, as Avan sneaked around the courtyard to the left, sending one of his midnight black spheres in sword form to the two women in the cage as he scurried past. Dani, with her enhanced ranger vision, noticed his form first, and nudged Jen, who was leaning against her, visibly exhausted, and immediately startled as well. They both glanced at Avan as the form came flying back in his direction, and he nodded to them, whereupon he could see a deep gratitude in the looks of both young women. A quick gesture with two fingers to his eyes followed in the direction of the houses further back brought him a hasty nod from his two team mates, which only reinforced his goal.
A quick thumbs up, which brought a frown to the faces of both women watching him, and Avan quickly strode on, while the guards just at that moment broke their encounter again.
As closely as possible and in as much shadow as he could, he continued to creep along the inside of the keep's wall until he reached the first house and sent his two meter wide sphere of influence through the interior. This house was an unused one, furnished with a bed, chair, table, and some unused candles.
The next houses on this side also showed similar results, differing only in that some interiors appeared to be tidy or recently used. 
Only when Avan reached the backmost stone house on the right, nestled against the inside of the outer wall, did he frown as he recognized the activity inside. Gritting his teeth and cursing inwardly, he ducked to one of the front windows and peered inside between the slits of the closed blinds. 'What else could vampires do?'

Inside, two vampires in robes similar to those worn by doctors, but in black, were drawing blood from a male occupant known to Avan with practiced posture and speed, dripping it through tubes into head-sized glass containers. Patris, visibly weakened and on the verge of his own physical breakdown from lack of blood, hung upside down on a wooden contraption while two tubes attached to either side of his neck slowly drained the viscous life fluid from him.