"Supes" (as he is referred to by no one but this poster) is an unnamed male commander of the Superfluous elves. He wears a t-shirt and has a dark, emo haircut, and is a member of the war council of the Royal Crown Coalition.Erf-b1-p49
As a member of the Royal Crown Coalition War Council, he was one of only four warlords at Ansom's table on the penultimate night of the siege; Erf-b1-p101 - the others being Duke Nozzle, Scarlet, and the Blue Warlord. Notably, there was no representative of the Marbits. There never seem to be representatives of the other elves, or Foxmud.
When Duke Nozzle and Scarlet decried Ansom for waiting to assault Gobwin Knob, S.W. offered a superfluous "Rrm." He seemed to take a bit more of an interest in the battle towards the end - when Ansom was sending in suicide waves against Lord Hamster's Uncroaked units in the Gobwin Knob Courtyard, the Superfluous Warlord called out after Ansom, "I do not trust you! We should have waited until Charlie could attack!" Erf-b1-p128