VIRD was involved in order to prevent Aryta siedge in Septentria by stiking from the rear with an amphibious attack, pierce the siedgers lines from the rear and reinforce the defenders. But they were waited by the artillery and suffered so much loss that, despite successfuly piercing the ennemy lines, they were too few to change anything. VIRD teams are described in the book by a YJ officer. In their functions, they are pretty close to the MRRF (and have a name close too) but the technology they have access to compared to the Frenchs and Belgians means they can deploy faster and with more means than their Ariadnan counterpart. At first, Immediate Reaction Divisions weren't meant to be Varunan troops only but they were those which were the closest fitted to the job at the creation of the divisions and so, were chosen to fill all the workforce of the divisions.