Defense of Rishi Station

The extragalactic planet Kamino's native species, the Kaminoans, were cloning experts. This led to them being hired by the Jedi Master Sifo-Dyas when he secretly went against the wishes of the Jedi High Council and decided to ensure the Galactic Republic had a military for the war he had seen in his visions. As a result, during the Clone Wars, Kamino was a major military target for the Confederacy of Independent Systems. Many sensor outposts were set up in order to scan the most likely routes to Kamino and monitor for a potential Separatist attack.

One such outpost was Rishi Station on the desolate Rishi Moon. Despite the station's importance, many of the clone troopers posted there, most of whom were rookies, who'd only recently completed their training, found life there extremely boring. The station was commanded by combat veteran Sergeant O'Niner, who spent a great deal of time reminding his men how important Rishi Station was to Kamino's defense. Among the troopers stationed there were the members of the training group Domino Squad: Hevy, Fives, Echo, Cutup, and Droidbait. Hevy was particularly adamant about the dull nature of the posting, wanting to fight on the front lines.

After the Battle of the Kaliida Nebula but still early in the war, the Separatists launched a plot to attack Kamino. The assassin Asajj Ventress had already infiltrated the ocean planet, while General Grievous planned to dispatch a force to take out the clones at Rishi Station and hardwire the station's all-clear signal so the Republic would be unaware of his passing invasion fleet. However, at the same time, two clone trooper officers, Commander Cody and Captain Rex, were conducting an inspection tour of various remote Republic military outposts, and after visiting the tracking station at Pastil, the Rishi moon was their next stop.

Under the cover of a meteor shower that caused Rishi Station to raise its deflector shields, a squad of BX-series commando droids descended to the Rishi Moon in Droch-class boarding ships. One vessel was noticed by deck officer CT-327 shortly after it landed, but before he could report the sighting, the droids ambushed and killed him. Inside, Sergeant O'Niner found he couldn't raise the sentry, and after Fives informed him that CT-327 was not on the scope, O'Niner sent Droidbait and Nub down to find him. They arrived in the hallway to the entrance to find the commando droids having just breached the doors, but only had time to report their presence before being shot and killed.

O'Niner grabbed a blaster and went to fight the droids, ordering his troopers to try and send a signal back to command before he, too, was killed. However, the droids had already disabled the station's beacon from outside. Cutup destroyed the controls of the door to the control room to slow the droids down, the troopers knowing they had to scatter. As the commando droids began to cut through the door, Fives, Echo, Hevy and Cutup escaped through a ventilation shaft that led to an area below the station, although Hevy was reluctant to go. When the commando droid captain was informed of the remaining clones' escape, it called them "cowards" before declaring that they didn't matter and ordering Rishi Station's all-clear signal hardwired.

Shortly thereafter, the Nu-class attack/transport shuttle Obex, which Commander Cody and Captain Rex were travelling in on their inspection tour, arrived in the Rishi system. When the starship hailed Rishi Station, the commando droid captain put on a clone helmet and modulated its vocabulator to sound like a clone trooper. It attempted to persuade Cody and Rex that an inspection was not required, and compounded the unconvincing impersonation by signing off with the well-known Separatist battle droid phrase "Roger, roger." With both officers now aware that there was something happening down on the moon, Cody told Rex that he was putting him in charge of the operation.

Fives, Echo, Hevy and Cutup emerged from the ventilation pipe a ways below Rishi Station. Cutup was almost immediately seized and eaten by a passing Rishi eel, to the horror of his squad mates. Fives fired at the eel with a DC-17 hand blaster he'd taken from the station, but to no effect. Shortly after, the rookie clones saw the Obex coming in for a landing, and knowing the danger the inspection team was in, attempted to contact them, but Echo was unable to reach them as the officers' comlinks were on a different scramble set. Disembarking from the shuttle, Cody and Rex brought additional DC-15A blaster rifles with them, and were shortly met by a commando droid disguised in clone trooper armor which emerged from the base. The commando droids had set up an ambush on the landing platform if they failed to persuade the officers to leave. The "trooper" attempted to persuade Cody and Rex that everything was completely normal on Rishi Station, but the wildly stilted body language and lack of an on-duty sentry were both suspicious, and the two demanded to be taken to the sergeant in command.

Below, after Echo reported his inability to reach the inspection team, Fives used a droid attack flare he had on him instead. Seeing the flare, Rex immediately shot the "clone trooper" in the head, removing the helmet after Cody's protestation to reveal that it was a commando droid, as he had suspected. The other commandos on the platform revealed themselves and attacked, forcing Rex and Cody to retreat down the platform. When the droids threw thermal detonators down the platform towards both clones and the attack shuttle, Rex decided that it was best to retreat off of the platform entirely. While the droids assumed Cody and Rex had been pulverized by the subsequent explosion, which destroyed the Obex, both officers used ascension cables to descend from the underside of the platform to solid ground beneath. They quickly encountered the three survivors, and Rex, recalling the commando droids' impersonation abilities, held the rookie troopers at blaster-point and ordered them to take their helmets off, to their confusion. After Fives, Echo and Hevy had removed their helmets, the Rishi eel from earlier reappeared, only to be killed by Rex with one shot to the eye. Afterwards, the clones were introduced to each other, and the officers identified the three as "shinies" due to their lack of battlefield experience, although Rex expressed hope for Hevy when the trooper stated they were ready to take back their base.

The five clones climbed up the side of the cliff towards the station. With the blaster rifles Cody and Rex had brought from the shuttle, Rex's own blaster pistols, and the pistol Fives had brought from the station, there were enough weapons for each trooper to have one. Rex's plan to get the station's blast doors opened, which Cody was skeptical of, involved taking out and impersonating the droid sentry left on duty outside the base, a task the Captain performed himself. The droids just inside the doors, not noticing Rex's customized armor, assumed him to be the sentry when they saw him walking up through the camera of the TT-8L/Y7 gatekeeper droid in a deliberately stilted fashion. Rex answered all the questions they asked him with "Roger, roger," although the droids noticed that his voice was slightly different from that of a commando droid's impersonation of a clone and assumed there was something off with the sentry droid's vocabulator. When asked to remove his helmet to prove he was a droid, Rex held up the detached head of the destroyed droid sentry to the camera, crouching below it. The droids also failed to notice that their comrade's eyes were not illuminated to indicate that it was active. The ploy succeeded in opening the door, and the three droids on duty at the door were quickly destroyed by the clones.

With Rex in the lead, the clones then stormed the station's control room, killing all of the commando droids present. The droid captain attacked Rex after he shot its blaster out of its hands, but he dodged its vibrosword strike and broke the droid's neck before slamming it into the floor. It was quickly discovered that the droids had hardwired an all-clear signal, preventing the clones from contacting the Republic about what had transpired.

Shortly thereafter, Grievous' fleet arrived in the space near Rishi, which the clones saw from the control room's window. Grievous attempted to contact the commando droids, but after receiving no response, dispatched a C-9979 landing craft with reinforcements down to Rishi Station. Having run out of time to try and repair the hardwired all-clear signal, Rex decided that the station should be blown up to cut the broadcast off and warn the Republic, and asked for every thermal detonator in the base's inventory. When it was pointed out that detonators would not be powerful enough, Echo suggested the highly volatile liquid tibanna, which was used to heat the base, as an alternate explosive. While Cody, Hevy and Fives went to the armory to secure weapons to defend the base, Rex and Echo moved the liquid tibanna, stored in PLNK-series power droids, into the control room and began setting them up to explode.

When the Separatist reinforcements attempted to gain entry to Rishi station, they were met by Hevy, wielding a Z-6 rotary blaster cannon and quipping that the droids hadn't said "please." He was quickly joined by Cody and Fives, and the three took out the initial wave of B1-series battle droids before retreating inside and resealing the door. In the control room, however, Rex and Echo were having technical difficulties with the detonator, as the handset they intended to use to detonate the tibanna remotely was not linking up to the detonator attached to the tanks. Running out of time as the droids had blasted open the main door, Rex asked Hevy to take a look at the detonator, which he promised he could fix quickly. As the others retreated down the ventilation shaft, Hevy, having trouble fixing the problem, decided to stay behind and ensure the bomb went off, even if it cost him his life, and hid in a hallway near the control room.

The battle droids, entering the control room, assumed the clones had retreated out of apparent cowardice, paying no attention to the plonk droids. After the other clones had emerged from the ventilation pipe, Rex attempted to order Hevy to detonate the bomb, only to discover he was not present, and immediately contacted him by comlink to order him to escape the base. Hevy refused, insisting that he knew what he had to do, and got into a fight with battle droid forces as he attempted to return to the control room. During the fight, he was injured after being shot in the shoulder. As he headed down the hallway to the control room, his blaster cannon jammed, and he took out a few more droids by throwing the now-useless weapon. Hevy was shot twice more in the back as he neared the detonator, and dragged himself over as he was surrounded by enemy droids. One droid asked if they took prisoners, and Hevy responded that he didn't before detonating the bomb, killing himself and destroying Rishi Station. Outside, Cody, Rex, Fives and Echo took cover from the falling debris, and Echo remarked that Hevy had always hated the base.

Aboard the Venator-class Star Destroyer Resolute, Jedi Generals Anakin Skywalker and Obi-Wan Kenobi, along with Admiral Wullf Yularen, had received Cody's report of his and Rex's visit to Pastil. However, when the two officers failed to check in from the Rishi Moon, both Jedi grew concerned, Kenobi moreso, although he quipped to his former apprentice Skywalker that perhaps his tendency to disobey orders was being picked up by Rex. Kenobi was also worried about Skywalker overreaching himself in his obsession with locating Grievous. However, the fact that Rishi Station was still transmitting an all-clear signal suggested to Kenobi that there likely was not a serious problem.

When the destruction of Rishi Station stopped the all-clear signal, Kenobi, Skywalker and Yularen, concerned, mobilized their fleet to immediately rush to the scene. On his flagship, Grievous was outraged, not having wanted his troops to destroy the station, and berated a battle droid who suggested that the destruction was a good thing. The arrival of the Resolute and its sister ships forced Grievous' outgunned fleet to retreat.

LAAT gunships were sent down to the Rishi Moon to sweep the area, and Cody, Rex, Echo and Fives were picked up by the Crumb Bomber. Afterwards, Fives and Echo were given medals for their service in the battle, as well as being inducted into the 501st Legion. Both troopers were uncertain about deserving the honor, but Rex and Cody reassured them that they had earned it.

The Separatists were forced to put off their planned attack on Kamino. Eventually, Grievous and Ventress led an attack on the planet's cloning facilities in Tipoca City in 21 BBY, but the attack was successfully repelled, with the two Separatist commanders achieving neither of their intended goals to steal the clone DNA sample or to destroy the facility.

Rex remembered Hevy's death for a long time afterwards, and took the time to reminisce about it, as well as the later death of Fives and the presumed death of Echo, during the Battle of Anaxes much later in the war.

The battle of the Rishi Moon first appeared in the Star Wars: The Clone Wars first season episode "Rookies."