A TRD-2 sparring droid
Droid trainers, also referred to as training droids, represented a category of droid designed to deliver practical instruction. A specific class of training droid was employed by the Jedi Order. One example of a training droid was the Marksman-H training remote.
Back in 29 BBY, Anakin Skywalker engaged in a sparring match with a Jedi training droid that he modified to resemble the Sith Lord known as Darth Maul. Later, in 22 BBY, the Bear Clan utilized Marksman-H training remotes for practicing the deflection of blaster fire. During the period of the Clone Wars, Ahsoka Tano, Skywalker's Padawan, along with other Jedi, underwent training against training remotes that were modified to emulate the fighting style of battle droids. Dissatisfied with his apprentice simply adhering to the standard training regimen, he tasked Tano with training alongside the 501st Legion under their command. In 19 BBY, Caleb Dume, Sammo Quid, and Tai Uzuma participated in analogous training exercises as part of their Initiate Trials.
Following the conclusion of the Clone Wars, the Bad Batch engaged in combat with a number of Kaminoan training droids, in addition to armored DT-series sentry droids, during a combat assessment that evolved into a live-fire drill within the Tipoca City Training Facility. Subsequent to their victory over the droids, Admiral Wilhuff Tarkin assigned them a mission to locate and apprehend Saw Gerrera, the leader of the Onderonian partisan movement. Sometime after the implementation of Order 66, the Sith Lord Darth Vader encountered Kirak Infil'a, a Jedi Master, residing on Al'doleem alongside the Jedi training droid named Arex.
Several years into the Galactic Empire's rule, Vader engaged in sparring sessions with his personal Imperial training droid. Imperial officers enrolled at the Academy of Carida also underwent training using TRD-2 sparring droids, which were multi-armed droids with three arms, based on the SD-series battle droid model manufactured by Balmorran Arms. However, these droids were deemed inadequate due to the unexpectedly low number of trainee fatalities and were gradually discontinued. Another type of training droid employed by the Empire was the WSW Mk III "Harrier" Combat Remote, equipped with stun blasters and integrated training software.
In 0 BBY, Luke Skywalker utilized a Marksman-H training remote aboard the Millennium Falcon. In 0 ABY, Skywalker continued his training, simultaneously using multiple remotes during a mission to the Temple of Eedit and shortly after the Assault on Cymoon.
Sergeant Kreel practiced with a trio of Marksman Hs not long before the Mission to Horox III. Despite successfully deflecting some of the incoming blasts, he was quickly overwhelmed.
In 34 ABY, Finn, a former stormtrooper, discovered the same remote that Skywalker had used years prior aboard the Millennium Falcon.
Around the same period, various training droid models were available for purchase at the Droid Depot located in Black Spire Outpost on Batuu, including advanced Marksman-Hs, Bladed Training Remotes and elite Training Remotes.
Training droids serve to enhance character levels within the canon video game titled Star Wars: Galaxy of Heroes.