Gorgon

"Like the Oracles and the Templar, the Gorgons reputedly possess the ability to define what is and is not real. Whatever they perceive becomes subject to erasure at their will. Until a countermeasure can be found, Guardians must avoid their gaze at all costs - or reply to any detection with immediate, overwhelming force."

- Grimoire description

The Gorgons are a group of nine (sometimes thirteen) unique Vex Harpy units reputed to reside within the Vault of Glass. They are described as being an "ontological weapon": beings capable of rewriting reality to their advantage. Their abilities are apparently limited to the Vault, however.

Gameplay
If a Gorgon detects a player (this includes shooting at them), the Gorgon will activate "Gorgon's Gaze", and the party has ten seconds before they are all killed instantly. Even if the players manage to kill the Gorgon within that period of time, the remaining Gorgons become stronger and more perceptive; this means killing them all would be a very difficult strategy. It is possible to kill all nine Gorgons at once, though generally only two or three will be destroyed. A way to avoid their gaze is to look at the ground until they move on.

Trivia
Gorgons were a mythological monster from ancient Greece, who were said to turn people into stone by looking into their eyes.
 * Up until Curse of Osiris, the Gorgons were the only Sol Imminent Harpies.

List of appearances

 * Destiny