Isosceles is an powerful being from outside The Box about 540 light-years wide. He is in fact so powerful that even He is interested in his powers.
Isosceles is a yellow, triangular creature that bears a strong resemblance to the reverse side of the Great Seal of the United States, which in turn consists of the Eye of Providence and an unfinished Egyptian pyramid. He has a single large eye rimmed with four short black lashes on its top and bottom. He moves around mostly by floating about, and rarely actually stands on his own two feet. He has thin, black limbs, wears a small, black bow tie, and has a tall, thin, black top hat that floats just above his head. His arms do not seem to be in any fixed position, and can be moved along his perimeter without any difficulty. He has also been seen carrying a small, black or yellow cane. Among the bottom part of his body is the pattern of a pyramid. When he gets mad, he turns red and his eye glows a light red. His exact age is unknown, we know he is at least a googleplex times older than our Box.