Castle Serenno

Located on the planet Serenno, Castle Serenno stood on its own grounds at the edge of a large cliff and was complemented by three ornamental gardens, each of which lay at the front of the palace. Those visiting the estate would walk down a long pathway situated in between the gardens to the front of the palace, where they were greeted by the 120-meter-high main tower where Count Dooku conducted most of his business. Ten relay buildings flanked the main tower, which featured a 22-meter-high stained glass window that looked out to a vast city in the valley below, while other buildings and defense outposts clung onto the cliff face. In front of the palace's main entrance was a double line of obelisks. By the time of the Clone Wars, the palace and the surrounding estate was protected by legions of Separatist battle droids.

The inside of the palace reflected Dooku's refined tastes. Luxuriously fitted, the finest furnishings and décor graced the palace's corridors. Artworks from across the galaxy adorned its walls, while statues from ages past looked silently on. However, the palace's lavishness on display for visiting dignitaries hid the cells and torture chambers located deep within the cliff face, in the levels where Dooku would conduct interrogations and executions. During the war, Castle Serenno served as not only the headquarters for House Serenno, but as a fortress for one of the Separatist's most prominent figures.

Around 102 BBY, Dooku was born. When Count Gora discovered that his second son, Dooku, was force-sensitive, he contacted the Jedi Order and left the young boy in a forest outside the palace, known to be inhabited by spine-wolves.

In 42 BBY, Count Ramil bought out the Abyssin mercenaries hired by the Great Houses of Serenno for protection from pirates and ordered them to invade Serenno and its capital city, Carannia. While the Abyssins were taking over Serenno, Ramil stayed in the palace with his droid army before leaving to force a surrender of the insurgents fighting the mercenaries in an effort to sort out Serenno by removing all the Great Houses of Serenno and framing Dooku of killing his sister, Jenza. This failed however and Ramil was killed by Dooku. Dooku then proclaimed himself as the new Count. The Great Houses after some convincing, agreed and requested a summit. After the Great Houses discussed where the summit was to take place given that Carannia was destroyed during the invasion, Dooku suggested that the summit could take place at Castle Serenno. The Great Houses agreed and a summit was held at Castle Serenno.

Around 23 BBY, Ventress was brought to the palace's great hall where Dooku was from the palace's balcony by LEP-10019. Ventress then met up with Dooku and after she was interrogated and tortured by Dooku with Force lightning for lying to him about her intentions to kill him, she was ordered to find Jenza, Dooku's sister. Ventress however questioned the order leading to Dooku to torture her again using Force lightning. Dooku later threw Data disks to a table in front of Ventress and ordered her to start looking in the Trannon district in the capital city, Carannia. Ventress then obeyed and left to complete the mission after Dooku warned her of what failure would bring. After completing her mission with Dooku saving her by killing the Republic agents coming to take Jenza offworld, Ventress experienced a vision where she was at the great hall of the palace. She then saw Dooku over a table with papers and data slates scattered all over the place, uncommon for the count. On the insistence of the ghost of Jedi Master Ky Narec, she walked closer to Dooku where she heard him muttering over why no one else could do as he commands. Ky Narec's ghost then questioned Ventress of following the man. Just before Ventress could reply, another figure resembling the Dooku that she knew came forward and verbally rebuked Ky Narec's ghost of being a disappointment and a failure. Ventress, unable to listen to Dooku criticising her previous master, ran to a forest near Castle Serenno, flooded with whispers of Ky Narec and Dooku before being transported to the Outer Rim planet Rattatak in her vision.

Early in the Clone Wars, an incident occurred at the Colonies planet Cato Neimoidia that caused at least 3200 civilians to die. This led to Count Dooku making a broadcast from his home condemning the Republic and claimed Separatist innocence. During the end of his broadcast, he dared the Galactic Republic to send Supreme Chancellor Sheev Palpatine to Cato Neimoidia to absolve the Republic of any guilt.

In 20 BBY, former Sith assassin Asajj Ventress and two other Nightsisters launched an assassination attempt on Count Dooku in order for Ventress to claim vengeance over her former master's betrayal of her. Arriving on Serenno aboard a GS-100 salvage ship, the three Dathomirians entered Dooku's palace and struck him with a poison dart in his bedroom to blind his sight, forcing him to engage the three in a lightsaber duel throughout the castle. However, despite their efforts, Ventress and her fellow Nightsisters failed as Dooku struck all of three of them with his Force lightning and threw them through the main tower window. Mother Talzin then brought Savage Opress to the palace to become Dooku's new apprentice. Dooku taught Savage that his anger gave him strength and that he had to feed off it to succeed. He then sent him on a mission to Toydaria to capture King Katuunko.

Later on, mastermind Moralo Eval constructed the Box, a structure designed to test a group of bounty hunters in order to assemble a team to kidnap Supreme Chancellor Palpatine, inside the palace grounds.

Later, Dooku summoned General Grievous to Serenno and ordered him to slaughter Ventress and the Nightsisters on Dathomir. Mother Talzin attempted to kill Dooku while he was in his base, which caused him terrible agony, but he contacted Grievous via comlink and ordered that he kill Talzin, instructing the general to follow the green mist in order to locate her. Dooku was saved by Grievous at the last moment. When he then believed that the Nightsisters were destroyed, he redirected his attention to his former apprentice Opress, who had betrayed him at the behest of Talzin. He summoned Grievous to his base and told him that he could sense that Opress was growing stronger each day. Although Grievous dismissed the fact that his former apprentice could be considered a threat, Dooku said he was a threat to all people, including them, and that something sinister was rising.

Following Dooku's death at the hands of Jedi Knight Anakin Skywalker during the Battle of Coruscant and the subsequent end of the Clone Wars after Order 66 and the Proclamation of the New Order, the castle was abandoned. At some point before 19 BBY the city located nearby was obliterated following an orbital bombardment carried out by the Galactic Empire who soon dispatched a task force to take over the castle and extract Dooku's war chest. The task force, comprised of more than forty clone stormtrooper led by Captain "Wilco," cleared the palace of everything valuable and loaded them onto three class four container transports so they could be taken offworld.

The operation was soon disrupted by Clone Force 99, a unit who had gone rogue after the war and become mercenaries, and tasked by the information broker Ciddarin Scaleback to steal as much as they could. They successfully infiltrated the extraction site, but three of their number, Tech, Echo, and Omega, were trapped inside Transport Three when Wilco ordered it to preemptively take off after noticing Force 99's leader Hunter lurking in the premises. The infiltration team attempted to escape the vessel via the escape pods, but the crew of the ship ejected them so as to strand the thieves on the ship. To return to the planet, the team boarded a container and detached it from the ship to use its emergency re-entry thrusters as a landing pod. Meanwhile, Hunter and Wrecker were engaged by Wilco's men and were forced to retreat inside the palace basement through a hidden turbolift. Although the squad was able to escape the palace grounds, the detached containers spilled their content on Serenno's surface, resulting in approximately 15% of the chest treasure to be lost.

This location first appeared in Nightsisters, the twelfth episode of the third season of Star Wars: The Clone Wars television series which aired on January 7, 2011. Concept art of the exterior of the main tower and the relay towers of Castle Serenno for "The Box" episode in the fourth season of Star Wars: The Clone Wars was done by Jackson Sze. The painting of Castle Serenno at night was also done by Jackson Sze for the episode. The lighting concept of the palace used in Star Wars: The Bad Batch season 2 episode "Spoils of War" was done by Molly Denmark.