UNDERTALE/Flowey

Overview
Flowey is the first and only living being without a SOUL in UNDERTALE. He attempts to kill the player at the beginning of the game.

Appearance
Flowey is literally a golden flower that has a face in the middle of it. He has the remarkable ability to imitate voices and faces and does so throughout the game. He imitates the player during the Neutral Route, Toriel during the Genocide and Neutral Routes, and Asriel (his former identity) before dying in the Genocide Route. He was created after a golden flower, injected with determination, was planted in Asgore's garden, where Asriel's ashes are.

Personality
He doesn't have a SOUL. How do you think he has a personality if he has no SOUL? Well, he does. He is very cruel and thinks the world is kill or be killed. He outright tries to kill the player after explaining this philosophy to the player at the beginning of the game.

Pacifist Route
He is seen in the beginning (duh) and at the end. If the player has befriended all monsters, seen the True Lab, and spared everyone, he absorbs the entire collection of the undergrounds monster SOULs (basically, he absorbs the soul of all the monsters you befriended), and returns to his true form Asriel. Asriel then introduces himself and battles the player. He can only be defeated by defeating the lost souls and by acting. He cannot be killed otherwise (unless you can hack).

Neutral Route
Flowey appears at the end and kills Asgore and his SOUL. He then absorbs the human souls and crashes the game. Opening the game again causes his battle as Photoshop Flowey to begin. He can then be spared or killed. Both cause the Neutral Route to end or continue as normal respectively.

Genocide Route
After killing Toriel, he sees you as Chara. He also tells his story as a flower in NEW HOME. And then he dies after he kills his former father.

Trivia

 * Flowey is the only monster or creature without a soul.
 * He is also the only monster that we know of who has come back to life
 * Naming the human Flowey causes the text, "I already CHOSE that name!" To appear, stopping you from using that name.
 * Flowey may be based off of the flower in Earthbound, which Toby Fox got inspiration from.