Description
(au details below)
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After his banishment from the dream realm, Grimm is too weak to sustain his physical form indefinitely. As a result, his physical body is stuck in an endless cycle of death and rebirth, as its lifespan is limited and its powers are limited
The Nightmare King, and his physical body, Troupe Master Grimm, are the same being separated by the barrier between the physical and the nightmare realms. They exist simultaneously, they share thoughts, memories and personality traits, although their physical appearance differs - the physical body is smaller, its body lacks the extensive fluff, and is more organic in nature. Within the nightmare realm and with the Nightmare Heart's power, Grimm has full control over the body's physical and physiological aspects, and so its appearance may change following each ritual if he so desires. However, each body withers away over time, and thus it must be replaced periodically. Unfortunately, with the Heart's limited power, the vessel must spawn in a reduced form and grow with the help of his troupe (or any volunteer). Collecting nightmare flame speeds up the process, as does the presence of the previous body, which then gets consumed by flame and replaced by the new vessel
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Stage I ("Grimmspawn") - the vessel that spawns from the nightmare flame. It is small in size, but capable of flight. Its legs and arms are underdeveloped, and its body is covered in fluff. Its eyes are closed, and the head is similar in shape to a teardrop, as the horns are not separated in this stage
Stage II ("Grimmchild") - having absorbed nightmare flame, the vessel grows in size and its limbs develop. The headshape resembles that of the final form, although its body is noticeably more serpentine in shape, and its fluff covering is more sparse. Consuming more flame allows it to continue growing until it reaches its final stage
Stage III ("Troupe Master") - after the previous vessel is consumed by flame, another takes its place. This form is most commonly known as the Troupe Master Grimm, or simply just Grimm. Despite its status as a vessel, it stands equal with the Nightmare King - it is with this body that Grimm is able to interact with the physical realm, and so this stage lasts the longest, up to a few months
However, in this form, Grimm requires blood in order to sustain his physiological functions for a longer period of time, as his heart and circulatory system are weak. Similarly, he rarely uses the full extent of his powers, as doing so weakens him and forces him to rest in order to regain his strength. Although he lacks the tail and the wings of his previous stages, his cloak can move around and warp into different shapes, most commonly into tendrils and spikes
Despite his weak heart, Grimm's body functions as you'd expect - he is capable of consuming and digesting food, and even reproduction (though the body is usually designed to be infertile, as a preventive measure). Interestingly, he is unable to cry, likely due to the unnatural aspect of his eyes
Stage IV - if the ritual is delayed for whatever reason, Grimm's body starts showing noticeable signs of decay. He becomes physically weak, he gradually loses his voice, and he starts shedding fur from his limbs. The flame rages from within his body, and smoke escapes through his wounds. His eyes lose their scarlet color and start leaking, making him appear as if he's weeping. The body eventually burns down, and if this occurs outside of a ritual, the next vessel is unable to consume its flame, meaning it takes a much longer time to grow. Grimm rarely allows himself to reach this stage, preferring to replace the body while it is still in a functioning state, as it makes the entire process much smoother