Emperor Palpatine has a new weapon—one that can annihilate a planet. But he's not targeting a planet—he's targeting the future of the Jedi, Leia's children. It looks like a hopeless situation for Luke Skywalker, who has the critical task of protecting the children. But it's not the first time Luke has found hope where none existed. The finale to the Dark Empire trilogy is collected here.
After perishing in battle with Luke and Leia Skywalker in Dark Empire, Emperor Palpatine was forced to occupy an inferior clone body. Unbeknownst to him, his personal physician had been suborned by Carnor Jax, backed by a number of other high-ranking Imperial personnel. The physician deliberately inserted genetic material and contaminants into all stored samples of the Emperor's original body, making these bodies far less resistant to the ravaging effects of the dark side than the original.
The last remaining clone body not destroyed by Skywalker or traitorous Imperials was now aging rapidly, and Palpatine's final, irrevocable end was near unless he could either fix his genetic material (impossible since no unadulterated samples remained) or insert his spirit into another body. After consulting with ancient Sith Lords on the mausoleum planet Korriban, Palpatine learned that Han and Leia's youngest child, Anakin, was the only workable body.
In an attack on Byss, the second Eclipse-class Star Destroyer, the Eclipse II, was steered into the Galaxy Gun by R2-D2, and a projectile from the Gun was shot into Byss, destroying it. Subsequently, Palpatine followed the Solos to Onderon and attacked Leia inside the Kira fortress, prompting Leia to fight back before realizing she was no match for the Emperor. Shortly after, Luke Skywalker arrived with his fellow Jedi. Rayf Ysanna was killed by a barrage of Sith lightning, and Empatojayos Brand was mortally wounded. Skywalker, stunned that Palpatine was going for baby Anakin Solo, looked on in shock, before Sidious was shot by a blaster bolt fired by Han Solo and sadistically rushed his cackling spirit towards the infant Anakin Solo. However, he was intercepted by the body of the dying Brand, who made the ultimate sacrifice as he died, willingly clasping his soul to Palpatine's, ensuring that both of them would be pulled into the netherworld of the Force (in Palpatine's case, Chaos). At long last, and with the assistance of all the Jedi of the past dragging him down, Emperor Palpatine was finally and truly killed.