Very much still in-development, especially visual design.

An immortal shape-shifting beast bound to the fate of Earth's caretakers; in most cases, humans. Has existed in some form since humanity's earliest days and appears mainly in times of peril. Embodiment of intentional carnage and the ferocity of nature. Compelled to work together with or protect humankind as a whole. One of several similar entities that represent different aspects of death.

Appears as a beast or a human the colours of blood and bone, can shift between the two and in largest form is a great red bird creature.

Specifically unique to the original setting they first appeared in (a dream I once had), they are dubbed "The Captain" by the boat crew they lead; a team assembled as humanity's first successful step at fighting back against the zombie hordes that struck the population down. In this setting they are a close friend to the lucid zombie James, having shared with him their knowledge in controlling the bloodlust of a monster around humans.

The Bones of the Earth

The aspects of death that the Captain belongs to are tied specifically to Earth. Depending on setting the details of their appearances are different, as well as whether people can percieve them or not. They are manifestation's of Earth's life force specifically and won't show up in settings with no Earth. All but Black Death (who is a herald of the unavoidable) and Blue Death (who by nature is unperceived) consider themselves teachers or guardians, willing to work together with humans (or other sapient beings from Earth) to avoid or pursue the things they embody.

• Blue Death - Death-as-life. The death unnoticed, the death omnipresent. The quiet death. A tick of the clock that cycles through seasons and lifespans. Usually appears as a dead blue weevil with holes for eyes that lead to a black void. Always awake, always active. Both the least and most powerful of all.
• White Death - Death-as-gift. The mercy kill, the soft oblivion, the easy path. The youngest. Appears as a humanoid dressed in white medical/religious garb, with piercing eyes and a half-veil or mask that covers sharp needle-like teeth. Uniquely tied to humanity, does not exist in times or settings with no sapient life.
• Red Death - Death-as-means. War, hunger, revenge. Death as the domain of violence, of poison and claw, of large scale conflict between and among species. Appears as a shapeshifting blend of apex predators in the colours of blood and bone. Always exists but awakens most strongly during events of great strife.
• Green Death - Death-as-change. The death of lands, the death of peoples and species. Appears as a huge wave in the land or sea, verdant green and bursting with life above and rotten and foul underneath. Awakens during environmental catastrophe, genocide, and natural disasters.
• Black Death - Death-as-end. Death unheeding, cold, final. Annihilation. A rarely awoken herald of mass extinctions, total destruction, and apocalypse. Appears as a gargantuan double wing-like structure of dark metal or stone, soaring slowly through the air. When the Earth finally ends, Black Death will be the last to go.