The Colossus, my personal warship and one of the most powerful in the Empire!
—Admiral Armos talking about his ship
The Colossus was an Imperial Star Destroyer that was used from 18 BBY right until its destruction in 10 BBY. It was fist controlled by Armos but when he died in 12 BBY his ship was given to Filus Peat who controlled it until the Colossus was destoryed in 10 BBY.
History[]
18 BBY–12 BBY: Creation and Early History[]
When the Galactic Republic was transformed into the Galactic Empire, Darth Vader ordered the creation of 25 Star Destroyers, one of which was the Colossus. A young man called Armos had just recently became an admiral so he was chosen to be the warship's commander. Despite the ship's owner being Moff Trevdar Halray, Trevdar never was on his ship.
The Colossus became involved in its first battle in 17 BBY. The Battle of Halm focused on the empire taking over the Confederacy of Independent Systems Fragment base on the planet Halm. The battle ended fast and had minor casualties for the empire. Later on, it was decided that the Colossus would be given additional spacecraft and troops. In 16 BBY, it was involved in a crucial battle that would hopefully end CIS fragments for good: a gigantic army was sent to Koru Neimoidia to wipe out the fragment's capital and a huge fraction of its navy. The battle ended with an Imperial victory and by 15 BBY, the CIS fragment was completely destroyed. It was sent to fight at the Battle of Jakku in 14 BBY, and the Colossus was put under the temporary control of Tiaan Jerjerrod while Armos was on another Star Destroyer. The Battle of Jakku was quick and easy.
12 BBY: Disaster at Zealand 6[]
The Colossus was sent to invade the planet Zealand 6 in 12 BBY, Armos was put in charge of a large fleet. The Empire were fighting against the military remnant of the Trade Federation called the Trade Federation Remnant. Despite the Remnant's navy being weak compared to the Empire's, their ground forces overpowered them. Armos went down to the planet and was killed. The Colossus was the only Star Destroyer that managed to escape the battle.

The Colossus above Zealand 6
12 BBY–10 BBY: Final years and destruction[]
Control of the Colossus was then given to Admiral Filus Peat. Filus was unable to fill Armos' place and the amount of battles the vessel was involved in was reduced. In 11 BBY, it was sent to Tatooine to drop off supplies to the local forces when it was boarded by space pirates. The pirates ran onboard the ship and grabbed valuable items to sell on the black market. Later that year, the Colossus went to Hoth to destroy a small army of Rebel stormtroopers. The Colossus was fatally shot by an enemy ion cannon but survived.
In 10 BBY, the Colossus docked at Coruscant to fill up on supplies. After Filus left the Colossus, a fire started in the back of the Colossus and quickly started to spread. It went unnoticed until it reacted with something and caused a huge explosion. The fire started to spread to several building, one of which Filus Peat was in. Filus was burned to death along with around 60 other people. The fire was put out eventually and a huge funeral was held for all the people that had died. All remaining parts that were salvaged of the Colossus were sold.