Continuity mistake: When Ahsoka leads a captive Cato to Jocasta and asks if she's all right, before they head off to call security, Ahsoka's lightsaber is absent from her belt in the first shot, but present in the second. (00:20:31)
Continuity mistake: The opening scene after the narration shows the end of "Cargo of Doom" again, focusing on the clone troopers, but the details are different, including Anakin and Ahsoka disembarking the shuttle with R2 and some of the clones removing their helmets before leaving, when that didn't happen in the previous episode.
Continuity mistake: Satine and her guards along everyone else who entered the shuttle at the end of the episode disappear - you can easily see inside the shuttle and through the other window.
Continuity mistake: When Obi-Wan duels Grievous on the bridge of his Arquitens cruiser, the cyborg General slashes up several computer consoles with some of his four lightsabers. Later, when Obi-Wan sends two clone officers to the bridge to try to detach the ship, the consoles are in the background with no visible damage.
Continuity mistake: When Rex is giving orders to the heavy cannons after the super-tanks emerge, his kama is missing.
Continuity mistake: Plo's lightsaber vanishes from his belt between shots when he takes Boba over to Hondo to see if the pirate can persuade the boy to reveal the location of the hostages. (00:19:05)
Continuity mistake: When Mixer and Redeye are first seen patrolling the Coronet's hold, their armour markings are visible in the first shot, but in the second, their armour is suddenly plain. (00:01:42)
Continuity mistake: After the newsreel, the episode's opening scene is of Grievous seeing Republic ships flying in to land and declaring that he needs to find an escape pod. But only in his second scene in the episode is Grievous informed that the transmitter on his escape pod is broken, prompting him to make that decision. (00:01:25)
Continuity mistake: When Mace and Ponds have the exchange that ends with the Jedi General dropping "I have a bad feeling about this", Ponds' kama (kilt) has a blue border instead of the usual maroon to match his armour. (00:08:43)
Continuity mistake: Ahsoka is wearing a red bodysuit for most of the episode, but when she falls to the floor after Bane shocks her unconscious, her legs are miscoloured a pale pink. (00:13:21)
Continuity mistake: When the Chancellor is being briefed on The Zillo Beast, Rex's kama is missing. (00:14:12)
Continuity mistake: When Padmé and Bail are walking down the hall after the Senate vote, the top of her right sleeve is miscoloured, with the purple section extending further down than it should on that outfit. (00:21:02)
Continuity mistake: During the opening briefing with Palpatine, Mace Windu and Yoda, Luminara Unduli attends via hologram. But during the shots where Obi-Wan is explaining the attack plan, and the shot over the shoulder of Palpatine's hologram looking at Obi-Wan and Ki-Adi-Mundi, Luminara is shown as being physically present (i.e. not a blue, translucent hologram). After Palpatine, Mace and Yoda sign off, she's back to being a hologram. (00:02:00 - 00:02:30)
Continuity mistake: After the first encounter with the zombie Geonosians, it's shown there are four clone troopers in the group when they retreat. When Obi-Wan orders two of the clones to try and head back to the surface to get reinforcements, there are suddenly several more clones present. (00:11:32)
Senate Spy - S2-E4
Continuity mistake: When Padmé accesses the holo-table with the droid factory plans, she puts her clutch purse on the edge of the table. After she guesses the correct password, the purse is absent from a shot facing her as the hologram activates, but present in the next shot. (00:15:56)
Continuity mistake: When Obi-Wan and Mace retrieve the stolen holocron at Black Stall Station, the device is shown as completely closed and back in a cube configuration. This is despite the fact that the previous episodes of the arc established that Jedi holocrons can only be opened by Jedi, and it was last seen partially opened after Bane inserted the data crystal, with no contact with any Jedi between Bane's escape and the arrival at his hideout. (00:15:08)
Continuity mistake: The canopies of Anakin and Mace's starfighters appear different than they did in the previous episode, now possessing an opaque rim around the outside.
Death Trap - S2-E20
Continuity mistake: When Commander Ponds orders some other clone troopers to evacuate because he's staying onboard with the Admiral, his kama (kilt) is missing, and his blaster pistols are missing from his holsters. (00:16:46)
Death Trap - S2-E20
Continuity mistake: When the alarm goes off, Sergeant Crasher tells his cadets that there's been an explosion and that they'll show the crew how the Clone Youth Brigade does things. As he's saying this, the camera cuts from him to a closeup of Hotshot before back to Crasher, who is walking through the same group of cadets in the exact same way in both shots. (00:10:36)
Continuity mistake: When Satine is falsely identified as a suspect in a shooting, she pulls her hand with her holdout pistol under her cloak, but when two police droids approach, her hand is back out again. (00:11:23)
Answer: Dooku never accepted Ventress as his apprentice, as far as I know; he just kept her as his devoted personal assassin. In Phantom Menace, it is stated that there can be only two Sith at a time, to prevent a power struggle in the lower ranks. To accept Ventress as an apprentice, Dooku would have violated that rule.