IG-88B was an IG-88 assassin droid from about 15 BBY to 3 ABY. He was the first replica to be activated by IG-88A in Holowan Laboratories.
After IG-88A gained "sentience programming" and killed much of theProject Phlutdroid personnel, IG-88B was activated, named by order of activation, and given the same sentience programming from the first unit. With the other IG-88s, as well as IG-72, the five droids managed to escape the factory and leave a swath of destruction in their wake.
In 6 BBY, IG-88B on a mission to kill Olag Creck encountered C-3PO and R2D2. The bounty hunter was captured but escaped and held the droids hostage.
IG-88B played a crucial role in the planned Droid Revolution on Mechis III by being thye main bounty hunter "face" of the group. He took jobs that often required massive amounts of destruction, in order to further lead pursuing Imperial forces away from Mechis III.
He was the unit that was contacted by Darth Vader to capture Han Solo. The Sith even aware of the order "dismantle on sight" concerning the droids, valued the capture of Han Solo too much to be concerned with the risks involved. While on board Vader's ship, IG-88B downloaded some of the ship's computer files, including information on the second Death Star, whic he transmited to IG-88A before departing. He then planted a tracer on Slave I and followed Boba Fett to Bespin, intent on killing him, There, he followed Fett to the bowels of Cloud City, where he walked straight into a trap set up by Fett. Four remotely activated ion cannons fired on IG-88B when he walked through a doorway. Boba Fett then shot him with a shoulder-mounted ion cannon, knocking him to the floor. He extracted IG-88B's own concussion grenades and placed them inside the droid's metal casing. The bounty hunter was blown from the inside out.
The last thing he heard was Fett's nonchalant remark to the watching Ugnaughts, "You're welcome to what's left".
Behind the scenes
IG-88B was played by Paul Klein on Star Wars: Episode V The Empire Strikes Back
Not to be confused with his "brother" IG-88A far more renown in the Expanded Universe and characterized by his desires to rule the world, some kind of a megalomanyac.
He makes appearances in different media such as the videogame Star Wars: The Old Republic and the Lego Star Wars series.