4. The Death Star
Other than the obvious character development threads in Episode II, the big connecting piece to the original trilogy in this prequel episode is the Death Star. In Attack of the Clone we discover another reason why Darth Sidious wanted a Separatist organisation in his pocket. With the droid armies, the Separatists had the numbers to keep the Jedi and the republic at bay for a while but behind the scenes Sidious was after the next step in his master plan. The Geonosians were weapon builders and in their catalogue they had the ultimate weapon: the planet destroying space station that would become known as the Death Star. Once the Separatist leaders were convinced there was a war splitting the galaxy in half and that the Republic had an army to battle their power, the Geonosian Separatist member Poggle the Lesser felt the need to step up their odds of winning. Handing the plans for the ultimate weapon to Count Dooku, the Battle of Geonosis and the start of the Clone Wars would be considered a victory for the Sidious no matter the outcome. Now he just had to take his time in the Senate while his ultimate weapon plans went into construction and at the right time all he had to do was switch the Republic over to an Empire and make sure he held onto that power with a planet destroyer he now had the plans for. As always Sidious manipulates every move in the game for his own advantage but the Death Star would make sure that all of his future plans were maintained and explains the importance of its construction and more so the significance of its unexpected destruction by the new kid on the block Luke Skywalker. From Palpatines move from Senator to Chancellor in Phantom Menace right through to the Death Stars reveal in New Hope, literally everything was mapped out or at least had a backup plan. Really this is a key theme in the prequels and an important point Lucas wanted to show us. After all, having Luke destroy the Death Star and undermining the might of the Sith-controlled galaxy in Episode IV was an impact in itself but via the prequels we are given a whole other chunk of weight to the situation and a real insight to just how unexpected a Skywalker sibling was to Palpatine and Darth Vaders hold on the galaxy.