The sentient forest of the puzzlebox, Arrived one day, in a warm way
A vertical flat space floating mere fractions of an inch off the ground, the 'front' surface of Forrest is unusually lumpy, sorta spiky at the same time, green shades of many hues, on closer examination, the observer would notice that the lumpyness is actually the canopy of many many trees all packed together tightly.
Forrest is the ultimate form of a Gestalt, millions of minds are melded to create his identity, not just the trees and smaller plants that are part of his base 'brain', but the insects, birds and other animals that reside within his self contained ecosphere.
Not too much is known about Forrest's past, only that he remembers Everything that has happened to him, over the course of eons, incredibly old, he is curious about the mess and it's inhabitants, as he has never actually interacted with other sentient creatures before arriving.
Forrest doesn't appear to be very technological, he is 100% natural, in fact, he is the very Essence of nature itself, even his ambulatory ability is not techologicaly based, When encountering technology, Forrest is usually curious, and confused about it's use in the Mess, and how it relates to himself.
Currently he is working with Trilogee on some manipulatory limbs, as he professed an idea that they would indeed, be quite handy