Is a user of Observation which grants them:
Observation (Varies between Unconscious Manifestation & Conscious Manifestation; Observation users consciously and unconsciously change truths around them creating Gods and demons from myths and rumors), Negation (The power of observation, has the ability to make something without form, be certain and stable, The Axiom, tasked humans with observing the universe, allowing humans to assign an answer to phenomena without an answer. Dagda mentions humanity's "understanding" (observation) is what's locked him and Danu in physical forms. Nanashi and his party's denial of YHVH cast him into a demonic form. Gods and demons exist within a human's observation. Demons that also exist beyond death can be killed by observation users), Negation of Personal Nonexistence (Ayin Physiology; Can kill The White and demons, who naturally exist within the expanse, which the Monochrome Forest exists within the expanse, a place that is eerily still, having no sound or smell, where even the ground itself feels unusual, which demons naturally exist in. The Forest also holds the White’s realm, which is a vast, white space), Negation of Incorporeality (Can harm and kill demons, who are beings made of data, that exist in a virtual world, along with being pure information. With even the most basic of objects in the verse existing as data), Negation of Abstract Existence (Conceptual, Primordial Source; Demons embody the phenomena and beliefs of humans, with their physical forms only being created due to humanity's observation locking them into these forms, and their true forms existing as the phenomena and beliefs they reside in), Negation of Acausality (Causality Immunity; Can harm and kill demons, who are natural residents of The Expanse, a place that transcends the past, present, and future of the multiverse, demons such as Ishtar are capable of going into separate multiverses, along into the "real world", demons such as Demi-fiend, can exist in different universes asides from the original SMT 3 universe, demons can exist even when the flow of time itself collapses and there is nothing left but a void), Negation of Invulnerability (Metaphysical Invulnerability; Observation users such as Raidou Kuzunoha the XIV, can harm demons with regular guns and swords, even though demons when brought into corporeal forms cannot be harmed by conventional weaponry, along with military grade weaponry[14]), Negation of Immortality (Ageless) & Resurrection (Atemporal Resurrection; It is noted by Lucifer that only a human can kill gods and demons, that when gods and demons try to fight each other the most they can do is seal each other. Permanently killed YHVH. All demons are reliant on the observation of humans to keep them existing, including even nonexistent demons such as The White, allowing them to come back even if they’re erased from existence and nonexistence), Negation of Dimensionless Existence (Non-Dimensional; Demons only have "forms" due to the observation of humanity with even some demons being in the lowest form of humanity's observation making them unseeable without help, the "true forms" of demons are in truth without the concept of form, without observation they are not certain nor stable, are a phenomena without an answer and are unbound by concepts such as truth completely unshaped by reality. Demons under their observation forms embody concepts such as infinity which they are free from in their true forms), Negation of Timeless Physiology (Demons are natural residents of The Expanse, a place that transcends the past, present, and future of the multiverse. Due to this, they do not apply by the speed formula and can appear anywhere they want in most cases), Timeless Physiology (Demons are natural residents of The Expanse, a place that transcends the past, present, and future of the multiverse. Due to this, they do not apply by the speed formula and can appear anywhere they want in most cases), Negation of Omnipresence (Observation can reduce one into a singular being, when the being was originally one that was everywhere within reality), Negation of Omniscience (Humanity's observation of YHVH defies his words and truths, YHVH is an all-knowing being that sets the fate of the entire world), Irreversible Damage (Nyarlathotep used a spear conjured by humanity's observation of a wound that can never heal to inflict a blow that could not be healed even by the strongest healing magic), Existence Grounding (Observation users can bring a demon or god's existence down to their level, such as when Flynn and his party's denial of YHVH as the one true god brought him to the level of a demon, massively weakening him. Dagda mentions humanity's "understanding" (observation) is what's locked him and Danu in physical forms), Power Bestowal (Gods & demons are granted by humans observations of them. To the point that a gods power is based off if humans still remember them. Observation has the ability to resurrect someone and give them strength to the point where they can fight Stephen with The Axioms powers), Power Nullification (Observation allows one to remove one's defenses and strengths along with some of their innate abilities), Reality Warping (Stephen stated that humans have the power to shape the world. Philemon states people have tremendous power in their souls over the flow of reality, with their strong wills being able to change reality), Conceptual Manipulation, Subjective Reality, & Creation (The power of observation, has the ability to make something without form, be certain and stable, The Axiom, tasked humans with observing the universe, allowing humans to assign an answer to phenomena without an answer), Truth Manipulation (Humans have the ability to change the answer they've found into faith, and eventually into truth. Observation debased YHVH's truths, removing him from everyone's mind, killing him), Memory Manipulation (Through the power of observation, the Persona 2 Innocent Sin cast were able to erase their meeting during a summer evening, creating an alternate timeline), Perspective Manipulation (The power of observation allowed humans to change the very design of the Abyss [the Expanse] to what they perceive it as[15]), Statistics Amplification & Resurrection (Observation has the ability to resurrect someone and give them strength to the point where they can fight Stephen with The Axioms powers. Isamu was able to survive a hit from Thor despite being a regular human), Statistics Reduction (Flynn and his party's denial of YHVH as the one true god brought him to the level of a demon, massively weakening him. One's will and beliefs can lower even a nonexistent entity's (such as The White) stats. Gods powers can be greatly reduced if they're forgotten. Observation allowed Aleph and his party to harm YHVH who stated as they were his creations, there blades cannot harm him, yet they were able to), Resistance to Memory Manipulation (Through the power of observation, the Persona 2 Innocent Sin cast were able to erase their meeting during a summer evening, creating an alternate timeline)
With their Willpower, they get: Sheer Will (Naturally users of willpower tend to have some of the strongest willpower in their respective universes), Statistics Amplification (A characters willpower in SMT allows them to increase greatly in strength allowing them to harm enemies they couldn't even scratch before and survive attacks that would have originally kill them, the will of one's friends and allies around them can invigorate one to become far more powerful then before), Regeneration (True-Godly; Characters that get completely erased by demons to the point that everything returns to nothing (otherwise known as returning to The Axiom) but with enough willpower one can regenerate back to life), Resurrection (Everyone praying for Raidou bolstered his willpower up, allowing him to resurrect and regenerate part of his body), Resistance to Pain (Users with high willpower can fight through pain that's so unbearable that it makes one unable to move, constantly take damage and being unable to control their demons well), Memory Manipulation (Noted by Polaris that all of the memories and relationships of the Devil Survivor 2 cast will be completely erased if they choose to restore the world, requiring a strong willpower to retain them), Empathic Manipulation (Humanity's willpower allows them to ignore the voice of God, with Zelenin needing to sing a stronger sword to wipe their willpower away), Truth Manipulation (Users with huge willpower can ignore the truths created by YHVH due to the bonds with their friends)