The Separatists invaded resource-rich Christophsis and imposed a blockade commanded by Admiral Trench to trap the Republic’s forces on the planet.

The blockade trapped Alderaan’s Senator Bail Organa, who had led a relief mission bringing food and aid to the people of Christophsis.

Anakin Skywalker used an experimental stealth ship to get through Trench’s blockade, rescuing Organa and reinforcing the Republic troops. But the Jedi immediately faced a furious ground battle for control of the planet.

The Republic also faced a hidden enemy – the clone trooper Sergeant Slick had been persuaded to betray his own side. Slick blew up Republic war materiel and ships before being caught by Captain Rex and Commander Cody.

While Slick prepared to strike, Asajj Ventress led Anakin and Obi-Wan Kenobi astray. The Sith apprentice then pursued a mission of her own while General Whorm Loathsom commanded the Separatist attack.

Loathsom’s battle droids were backed by fearsome octuptarra droids and columns of AAT battle tanks. The Republic countered with AV-7 artillery.

Loathsom’s biggest asset in the Christophsis assault was a portable shield generator whose field protected his forces against the AV-7s. That allowed Loathsom to move his troops steadily forward without fear of Republic artillery barrages.

During the fighting, a Republic shuttle landed with an unexpected visitor. The Padawan Ahsoka Tano came from Coruscant, sent by Yoda with orders that Anakin serve as her master. Anakin objected that a Padawan would only slow him down, but reluctantly did as Yoda asked.

Anakin and Ahsoka slipped through the Separatist lines by hiding on the battlefield, then battled Loathsom’s droids in a desperate bid to destroy the shield generator.

Meanwhile, Obi-Wan tried to hold the Republic line and prevent the AV-7s from being overrun. The famed Jedi negotiator went so far as to surrender to Loathsom and draw out the terms of his capitulation, stalling to buy time for Anakin and Ahsoka.

The gambit worked – barely. The Jedi reached the shield generator and blew it up, allowing the AV-7s to rain devastating fire on the now-unprotected Separatist forces.

Meanwhile, Republic warships in orbit above Christophsis had punched through the Separatist defenses. The battle for the crystal planet had been won.

Later in the Clone Wars, the Separatists tried to avenge their earlier defeat with a strike at Christophsis – which gave Quinlan Vos and Asajj Ventress a chance to try and assassinate Count Dooku.

But Vos had his own agenda, and hoped to use Dooku to target Darth Sidious himself. The assassination attempt turned into a chaotic battle, with Republic forces shelling the Separatist headquarters in a desperate attempt to kill Dooku. When the fighting on Christophsis ended, Dooku had escaped, Vos had narrowly escaped falling to the dark side, and Ventress was dead.