Ouroboros

Ouroboros are the embodiment of eternity. Though they're prevalent as a symbol, often scrawled across the margins of alchemical tomes, few know that the beasts actually exist in the Astral Plane, where they fly through the silvery-gray void like a serpentine wheel. The ouroboros is usually depicted as a snake devouring its tail. This circular symbol is synonymous with infinity, self-sufficiency, and eternal unity.

An ouroboros' form exemplifies the unfathomable concepts of forever. Its undulating body is composed of smaller serpents, who are in turn composed of ever smaller serpents, continuing indefinitely. These smaller components are recycled as the ouroboros devours its tail, existing in a perpetual, cyclical process of creation and destruction. It is a massive creature, forming a loop roughly 50 feet in diameter and weighing hundreds of tons.

An ouroboros's most striking feature is its ability to almost instantly grow new flesh and heal from nearly any wound. This profound regenerative ability comes in part from an ouroboros's magical blood, which is rumored to have many miraculous properties.

Through their inscrutable behavior suggests that an ouroboros is mindless, the creatures boast crude intellects and can understand speech, though they have no way to speak. They possess an instinctive, almost obsessive will to survive and defend themselves ferociously if threatened in even the slightest way. Often these perceived threats take the form of another creature simply existing within the ouroboros's line of sight, leading other Astral creatures to give these powerful beings a wide berth. The only creature an ouroboros reliably ignores is another ouroboros, but they're so incredibly rare that these meetings occur only once an age.

Being entirely self-sustaining, an ouroboros rarely deigns to emerge from its consumption to engage with the Material Plane. Yet, the creature remains capable of inflicting tremendous devastation that far surpasses what it could wreak leveraging only its massive size alone. Left to its own devices, an ouroboros is likely to simply roam the Astral Plane in eon-spanning cycles, following some pattern too long and large for any mortal to even chart, much less fully comprehend. When conjured to the Material Plane, however, an ouroboros eagerly begins to initiate the cycle of renewal for which it is best known, beginning with that cycle's first step: destruction.