R.A.T (Roblox Assault Team) is the second largest group in Roblox. It was previously originally lead by ColourTheory, but is now led by the Councilium, which is a small group of people who have joint ownership. The Vaktovian Empire and the Roblox Assault Team had a war which was one of the most famous in the roblox clan world, however, the victor is unknown as both groups say they won, and along with that, there were so many raids, and not all victories were accounted for, so nobody truly knows who won the war. There are heated debates on the winner to this day.
Recently, ColourTheory came back to Roblox to rebel against cj10127's new leadership of R.A.T. ColourTheory called the issue with the current R.A.T an "incompetent administration." To help his rebellion, ColourTheory created a new group called The New Frostarian Union, which holds many high ranks from R.A.T and many other members who want R.A.T to go back to the way it was. The rebellion was a success, and now, cj and Colourtheory, as well as others, all cooperate to run R.A.T, with the other R.A.T who helped to rebel gaining back their previous ranks.
2nd RAT-VAK war
After the Vaktovian Empire's success with the dragged out war with TGI, Vaktovia's high ranks decided to attempt to wage war on R.A.T, consistantly raiding R.A.T's base, Fort Celeste II. Within days of attacks on R.A.T's base, R.A.T accepted the declaration of war, and official war terms were created. (Found here: http://www.roblox.com/Forum/ShowPost.aspx?PostID=131405820)
It did not take so long for Vaktovia to prevail. Though the last war was a draw, the second time around, VAK won.