A clone of Halagad Ventor was created by the mad genetic terrorist Zeta Magnus during the early months of the Clone Wars.
In the decades preceding the Clone Wars, the mutant Zeta Magnus escaped his Arkanian creators and wandered the galaxy. Shortly after he discovered his creators had programmed an expiration date into his genetic code, the Sith Lord Darth Sidious approached him with an offer of immortality in exchange for his fealty. While Zeta agreed to lend his genetic talents to Sidious and his subordinates, he didn't trust him at all and planned to kill the Dark Lord if he failed to uphold his promise. After Zeta helped develop various bioweapons for the Separatists during the Clone Wars, he decided to annul his contract with Sidious. In 22 BBY Zeta Magnus plagued the S'kytri people and declared himself the Magister of their homeworld Skye in order to provoke a response from the Jedi. When Jedi General Obi-Wan Kenobi and Jedi Commander Anakin Skywalker were dispatched to stop him, Zeta Magnus's agents acquired analysis-grade blood and tissue samples of the two Jedi from a restricted medical source.
In the laboratory of his opulent fortress atop the Canaitith Mountain on Skye, Zeta Magnus began to grow a clone of Anakin and Obi-Wan. Zeta used modified Arkanian GeNode cloning technology in conjunction with forgotten he acquired from the abandoned cloning lab under the Jedi Enclave on Dantooine to create two stable clones of the Jedi in mere days. By the time Anakin, Obi-Wan, and Jedi Knight Halagad Ventor reached the fortress and were captured, the clones had grown to the equivalent age of ten standard years. Since the clones were nothing more than mindless husks, Zeta Magnus placed Mindscan droids on the Jedi's heads to scan their minds. Once their scans were complete, the droids would flash-pump all of the Jedi's memories to their clone's minds. To ensure the clone's loyalty and subservience, cyber-mnemonic implantations would be installed that gave Zeta Magnus total control over their minds and turned them into obedient drones. Since the midi-chlorian count of the clones were the same as their templates, Zeta Magnus would have two fully trained Force-sensitive Jedi at his disposal.
At the time of the Jedi's capture, only the clones of Obi-Wan and Anakin had been growing. While the three Jedi were knocked out for thirty minutes from a stun blast, Zeta Magnus collected genetic material from Halagad and began to process it. Zeta Magnus revealed that he had been instructed to kill Kenobi and Ventor so young Skywalker could flourish under his benefactor's guidance. Instead of killing the two Jedi and returning the Chosen One to Darth Sidious, Zeta planned to create three obedient Jedi slaves and return a clone of Anakin to Sidious. While Anakin served as Sidious's confidant, the Sith Lord would be ignorant to the fact that his protégé was actually a clone agent of Zeta Magnus.
Once the mind scans were complete, Zeta Magnus prepared to execute the three Jedi with his vibro-ax. The Force-sensitive S'kytri Kharys used the Force from outside the laboratory window to pull the mutant's blade so it struck the torture droid that was preventing the restrained Jedi from using the Force. Once the Jedi freed themselves they began to fight Zeta Magnus and his four Thyrsian clones. Zeta Magnus's commandos attempted to throw a Class-D detonator at the Jedi's position, but Ventor used the Force to detonate it in his hand. The disruptor detonator annihilated the area of the lab where the commandos stood and disintegrated the clones of Anakin, Obi-Wan, and the tank that would hold Ventor's clone.
The clone of Halagad Ventor first appeared in the novella SkyeWalkers: A Clone Wars Story by Abel G. Pena.