The Tan Storm Legion was the Tan Army division fighting the Green at the beginning of the Strike campaign
Under the command of Colonel Destruction, the Storm Legion subdued the Greens until the Commander returned and tipped the balance in their favor just before total destruction.
In a very short time the Greens managed to gain ground in the house where the conflict took place, and after a few years they managed to retake the house and the neighborhood. The Storm Legion was replaced by the Red Army.
Even today, however, some remnants are often found collaborating with the Reds, as in the Red Alert conflicts. But they are not usually a problem.