What describes a person who knows everything or has unlimited awareness?

The term that best describes a person who knows everything or possesses unlimited awareness is "omniscient." This word comes from the Latin roots "omni," meaning 'all,' and "scient," meaning 'knowing.' In various contexts, especially in literature and discussions relating to knowledge, an omniscient being is one that has complete and infinite knowledge, often used to refer to a narrative voice that knows all characters' thoughts, feelings, and backgrounds.

The other options, while they have their meanings, do not convey the same sense of all-knowingness. For instance, someone who is scrupulous refers to being very attentive to detail, especially in ethical matters, but does not imply comprehensive knowledge. The term invulnerable describes someone who cannot be harmed or affected, and while it suggests a certain unassailability, it does not relate to knowledge. Uncanny refers to something that is mysterious or strange, often in a way that is unsettling, but again, it does not imply any specific awareness or knowledge capability. Hence, "omniscient" is the most fitting term to describe a person with such extensive awareness.