Title: Star Wars: Episode III – Revenge of the Sith (video game)
Content:  talent for the animated version of Count Dooku, voices various minor characters as well as Dooku himself. General Grievous is voiced by Matthew Wood, who also provided his voice in the game's film counterpart and the 2008 Clone Wars series. Terrence C. Carson voices Mace Windu and Nick Jameson voices Chancellor Palpatine/Darth Sidious and Ben Kenobi. Scott Lawrence, best known for his role as United States Naval JAG lawyer Cmdr. Sturgis Turner on the CBS series JAG provides the voice for Darth Vader. Yoda and Cin Drallig are both voiced by Tom Kane, who also provides additional voices. Finally, Serra Keto is voiced by Kari Wahlgren.
Title: Vader Episode I: Shards of the Past
Content: Dupree Jones as Darth Vader ; Jesse Gomez as the voice of Darth Vader ; Star Wars Theory (Neo) as unmasked Darth Vader ; Marik Knight as Young Anakin Skywalker ; Steven Bartlett as Emperor Palpatine ; Bradley Klein as the voice of Emperor Palpatine ; Catherine LaSalle as Padmé Amidala ; Andrew Branch as Commander Fox 
Title: Darth Vader
Content:   Darth Vader was portrayed by bodybuilder David Prowse in the original film trilogy, with fencer Bob Anderson performing the character's lightsaber fight scenes. At 6ft 6in tall, George Lucas thought Prowse "brought a physicality to Darth Vader that was essential for the character ... with an imposing stature and movement performance to match the intensity and undercurrent of Vader’s presence." Lucas chose to have a different actor be the voice of Vader, since Prowse had a strong West Country English accent that led the rest of the cast to nickname him "Darth Farmer". Lucas originally intended for Orson Welles to voice Vader, but after deciding that Welles's voice would be too recognizable, he cast the lesser-known James Earl Jones instead. Jones initially felt 
Title: Darth Vader
Content:  it. They trained extensively with stunt coordinator Nick Gillard to memorize and perform their duel together. As in the previous prequel film, McGregor and Christensen performed their own lightsaber fighting scenes without the use of stunt doubles. Anakin has also been voiced by Mat Lucas for the 2003 micro-series Clone Wars, and by Matt Lanter in the CGI animated film The Clone Wars, the television series of the same name and for Anakin's small roles in the animated series Rebels and Forces of Destiny. James Earl Jones reprised the voice role for Vader's appearances in Rebels. Both Lanter and Jones contributed their voices for the second-season finale of Rebels, at times with identical dialogue spoken by both actors blended together in different ways.
Title: Darth Vader
Content:  the NPR/USC radio series. Both Spencer Wilding and Daniel Naprous portrayed Vader in Rogue One (2016), with Jones reprising his role as the character's voice. Vader's character has also been portrayed in several video games; in games such as Rebel Assault II: The Hidden Empire and Dark Forces, visual effects artist C. Andrew Nelson appears in short sequences in the Vader costume, voiced by Scott Lawrence. Matt Sloan, who appeared in the YouTube parody Chad Vader, provided the voice of Darth Vader in The Force Unleashed. As a result of his video game appearances, Nelson was cast to appear as Vader in brief sequences inserted into the Special Edition of The Empire Strikes Back, in which Vader is seen boarding his shuttle.
Title: Star Wars: Episode III – Revenge of the Sith
Content:  his role from previous films as the voice of Darth Vader. Director and Star Wars creator George Lucas has a cameo as Baron Papanoida, a blue-faced alien in attendance at the Coruscant opera house. Lucas' son Jett portrays Zett Jukassa, a young Jedi-in-training. One of Lucas' daughters, Amanda, appears as Terr Taneel, seen in a security hologram, while his other daughter Katie plays a blue-skinned Pantoran named Chi Eekway, visible when Palpatine arrives at the Senate after being saved by the Jedi and talking to Baron Papanoida at the opera house. Christian Simpson appeared as a stunt double for Hayden Christensen.
Title: Star Wars (film)
Content:  the voice of Darth Vader. Lucas originally intended for Orson Welles to voice the character after dismissing Prowse due to his West Country English accent (which led to him being nicknamed, within the cast, as "Darth Farmer"). However, determining that Welles' voice would be too familiar to audiences, Lucas instead cast then-relatively less recognizable Jones.  Other actors include Phil Brown and Shelagh Fraser as Luke's Uncle Owen and Aunt Beru; Jack Purvis, Kenny Baker's partner in his London comedy act, as the Chief Jawa in the film; and Eddie Byrne as Vanden Willard, a Rebel general. Denis Lawson and Garrick Hagon played rebel 
Title: Ben Burtt
Content:  made using an ARP 2600 synthesizer, as are some of the squawks made by the tiny holographic monsters on the Millennium Falcon spacecraft. In Star Wars: Episode III – Revenge of the Sith (2005), Burtt's provided the voice for Lushros Dofine, captain of the Invisible Hand cruiser. The heavy breathing of Darth Vader was created by recording Burtt's own breathing in an old Dacor scuba regulator. Burtt used the voice of an elderly lady that he had met in a photography shop for the voice of E.T. the Extra-Terrestrial. The woman's low pitch was the result of very heavy smoking, specifically Kool cigarettes. Burtt created the "voice" of the title character and many 
Title: Star Wars: Episode III – Revenge of the Sith
Content:  as the voice of Yoda, a Jedi Grandmaster and the leader of the Jedi Council.   Peter Mayhew, Oliver Ford Davies, Ahmed Best, and Silas Carson reprise their roles as Chewbacca, Sio Bibble, Jar Jar Binks, and Nute Gunray and Ki-Adi-Mundi, respectively, from the previous films. Joel Edgerton and Bonnie Piesse also make cameo appearances, reprising their roles as Owen and Beru Lars respectively from Attack of the Clones. Sound engineer Matthew Wood provides the voice of General Grievous, the fearsome cyborg commander of the Separatists' droid army. Temuera Morrison portrays Commander Cody and the rest of the clone troopers. Bruce Spence portrays 
Title: Rogue One
Content:  C-3PO, and R2-D2, respectively; Vee is uncredited for his role. James Earl Jones also reprises his role from previous films as the voice of Darth Vader, who is physically portrayed by Spencer Wilding during the meeting with Krennic and aboard the Star Destroyer, and by Daniel Naprous for the end scene. Grand Moff Tarkin and Princess Leia Organa are played by Guy Henry and Ingvild Deila, respectively, with the digital likenesses of Peter Cushing and Carrie Fisher superimposed. Henry also provides the voice for Tarkin, while archival audio of Fisher is used for Leia. Angus MacInnes and Drewe Henley are featured as Gold Leader Dutch Vander and Red 

Question: who did the voice of darth vader in episode 3?
Answer: Hayden Christensen.