Heavy Trooper

The Clone Heavy Trooper, also known as an ARC (Assault Recon Commando) Trooper, is trained personally by Jango Fett to be the elite of the Republic's armies. Bred to have more independence than the other troopers, they are used on specialized missions where other Clones would fail or falter. Their supreme knowledge of the various weaknesses of the Seperatist vehicles leads to them be equipped with a rocket launcher more often than not, though they are proficient with pretty much every known weapon. In addition to their normal armour, ARC troopers wear blue skirt-like clothes, to seperate them from the others.

Note: This is based on information in Star Wars Battlefront. This is all my own words, but the general idea comes from that game. Due to limitations in what the developers could do, thewy only used them as rocket-troopers, instead of an "every-weapon killing machine".