Walkers formed the backbone of the GDI military in the Second Tiberium War, following aforementioned research and development. The Humvee was superseded by a Wolverine Powered Combat Suit with twin automatic cannons on its arms with recon as its role. The M1 Abrams was replaced with the Titan Medium Mechanized Battle Walker with an 120mm APDS side-mounted cannon. The Titan had a fairly long range and was often used to take out Nod defenses beyond their range. However, the technology was still being further developed, as the mighty Mammoth Mk. II was being developed and first units fielded at the time.