Flowey

Flowey (/ˈflaʊi/ ) is the first major character that the protagonist encounters in Undertale, serving as the main antagonist for the majority of the game, specifically the Neutral and True Pacifist routes. He provides an introduction to the mechanics of encounters by sharing "friendliness pellets," which are actually harmful bullets. His main philosophy is "KILL or BE KILLED."

Appearance
Flowey usually appears as a sentient, grinning, golden flower, with a white androecium, six yellow petals, and a light-green stem. Flowey can contort his face into a variety of expressions and mimic the faces and voices of other characters. He mimics Toriel and Asgore in some situations, as well as his old self at the end of the Genocide Route. He also mimics the protagonist's face before the Neutral Route's final battle.

Personality
Initially, Flowey operates under a façade of friendliness and politeness. He often greets the protagonist with "Howdy!", calls himself "your best friend," and, like his father, appends polite words such as "gosh" and "golly" to the ends of his sentences. Whenever he drops this guise of friendliness, he often calls the protagonist an "idiot."

Flowey has a malevolent and cruel disposition, berating the protagonist for not following his "kill or be killed" philosophy. Despite this, he also criticizes the protagonist at the end of the Ruins if they killed any monster. He is manipulative, devious, and a cunning planner and subtle if the circumstances require it. He retains his memories between SAVEs because he was once able to SAVE. He is also shown to be extremely cowardly, as he kills his former father to appease the protagonist in a vain attempt to save his own life in the Genocide Route's conclusion.

Ruins Start
Flowey introduces the concept of the bullet board and calls his bullets "friendliness pellets." When the protagonist runs into his bullets, he announces his central philosophy. Regardless of whether the protagonist dodged Flowey's bullets or not, he then attempts to kill the protagonist with an unavoidable ring of bullets, but Toriel intervenes and saves the protagonist.
 * If the protagonist dodges three times, his friendly act slips and he hypocritically snaps at the protagonist for toying with him.
 * The background music lowers by one semitone each time the bullets are dodged, before slowing, lowering pitch, and stopping entirely.
 * Before his third attack, Flowey screams "RUN. INTO. THE. BULLETS!!!" before quickly changing the "BULLETS!!!" in the speech bubble to "friendliness pellets."

If the protagonist killed Flowey on a previous Neutral Route, he will not appear. If the protagonist spared him, he reminds the protagonist not to kill anyone. If the protagonist gained no EXP, he reminds them to befriend everyone. After resetting a Neutral Route multiple times and repeating Flowey's initial encounter, he becomes annoyed and questions if "you have anything better to do."

Ruins End
At the exit to the Ruins, Flowey judges the protagonist's actions up to that point. Flowey does not appear to judge the protagonist if he was killed in a previous Neutral Route. {{Dropdown|

If The Protagonist Spared Toriel

 * (If they have earned EXP)
 * Clever. Verrrryyy clever.
 * You think you're really smart, don't you?
 * So you were able to play by your own rules.
 * You spared the life of a single person.
 * Froggit, Whimsun. Vegetoid, Loox. Migosp, Moldsmal.
 * Think about those names.
 * Do you think any of those monsters have families?
 * Do you think any of them have friends?
 * Each one could have been someone else's Toriel.
 * Selfish brat.
 * Somebody is dead because of you.
 * (If they have not earned EXP)
 * I bet you feel really great.
 * You didn't kill anybody this time.
 * But what will you do if you meet a relentless killer?
 * You'll die and you'll die and you'll die.
 * Until you tire of trying.
 * What will you do then?
 * Will you kill out of frustration?
 * Or will you give up entirely on this world...
 * ...and let ME inherit the power to control it?
 * I am the prince of this world's future.
 * Don't worry, my little monarch, my plan isn't regicide.
 * This is SO much more interesting.
 * (If the protagonist killed Toriel before)
 * Clever. Verrrryyy clever.
 * You think you're really smart, don't you?
 * So you were able to play by your own rules.
 * You spared the life of a single person.
 * But don't act so cocky.
 * I know what you did.
 * You murdered her.
 * And then you went back, because you regretted it.
 * Ha ha ha ha...
 * You naive idiot.
 * Do you think you are the only one with that power?
 * The power to reshape the world...
 * Purely by your own determination.
 * The ability to play God!
 * The ability to "SAVE."
 * I thought I was the only one with that power. But...
 * I can't SAVE anymore.
 * Apparently YOUR desires for this world override MINE.
 * Well well.
 * Enjoy that power while you can.
 * I'll be watching.

If The Protagonist Killed Toriel

 * (First time)
 * I hope you like your choice.
 * After all, it's not as if you can go back and change fate.
 * In this world, it's kill or be killed.
 * That old hag thought she could break the rules.
 * She tried so hard to save you humans.
 * But when it came down to it...
 * Hee hee...
 * SHE COULDN'T EVEN SAVE HERSELF.
 * WHAT AN IDIOT!!
 * (Second time)
 * Ha ha ha ha ha...
 * You disgusting animal.
 * You didn't even TRY to spare her.
 * (Subsequent times)
 * Wow, you really can't get enough.
 * You kind of remind me of myself.
 * (If Toriel was spared before)
 * Wow, you're utterly repulsive.
 * You spared her life...
 * Then you decided that just wasn't interesting enough for you.
 * So you murdered her just to see what would happen.
 * You killed her out of boredom.
 * Truly disgusting...
 * Ha ha ha ha...
 * You naive idiot.
 * Do you think you are the only one with that power?
 * The power to reshape the world...
 * Purely by your own determination.
 * The ability to play God!
 * The ability to "SAVE."
 * I thought I was the only one with that power. But...
 * I can't SAVE anymore.
 * Apparently YOUR desires for this world override MINE.
 * Well well.
 * Enjoy that power while you can.
 * I'll be watching.

If Genocide Route Requirements Are Met
}}
 * Hahaha...
 * You're not really human, are you?
 * No. You're empty inside. Just like me. In fact...
 * You're &lt;Name>, right?
 * We're still inseperable, after all these years...
 * Listen. I have a plan to become all powerful.
 * Even more powerful than you and your stolen soul.
 * Let's destroy everything in this wretched world.
 * Everyone, everything in these worthless memories...
 * Let's turn 'em all to dust.
 * An audio clip then plays of Flowey exclaiming "That's a wonderful idea!"
 * Flowey's Judgments

Neutral Route
After the Ruins, Flowey will be seemingly absent until the end of Asgore's battle. However, backtracking in some rooms allows the protagonist see Flowey burrowing back into the ground on the edge of the screen.

Flowey also leaves a message on an Echo Flower in the vertical room before the bridge in Waterfall that changes if the protagonist spared or killed Toriel.

If the protagonist decides to kill Asgore, Flowey appears, destroys Asgore's SOUL, and absorbs the six bottled human SOULs. If the protagonist spares Asgore, Flowey appears and kills Asgore himself. Then, the game crashes and Flowey's battle begins.

After he is defeated, the protagonist has the chance to spare or kill Flowey. Flowey requires the protagonist to offer him mercy multiple times before he flees, unsure why the protagonist is being nice to him.

If the protagonist loads or finishes another Neutral Route, Flowey does not absorb the SOULs because he knows that they would rebel again. Instead, the protagonist will be able to exit the room and receive Sans's Neutral Route phone call.

If spared after his battle, Flowey will advise the protagonist during subsequent Neutral Routes. If the protagonist gained EXP before his battle, he asks the protagonist to prove his philosophy wrong, as he thinks it may be meaningless. Flowey also offers unique dialogue if the protagonist only killed Asgore and tells the protagonist that they wasted everyone's time. If the protagonist earned no EXP, yet they have not met all the requirements for the True Pacifist Route, he mentions that the protagonist should get closer to one of the main characters, depending on who they previously befriended.

The protagonist can then recover their previous SAVE file and follow his advice.

If the protagonist kills Flowey, he recognizes that the protagonist can kill before becoming "just a regular flower."

If he was killed after his battle, Flowey will not leave a message for the protagonist after the credits close, and, after a reset, will not appear until after the resolution of Asgore's battle. Flowey then berates the protagonist for thinking that killing him solved anything. He explains that he was brought back when the protagonist loaded their SAVE file and that they still cannot achieve their happy ending.

If the protagonist nearly completes a Genocide Route but resets after killing Undyne, Flowey becomes upset with the protagonist. However, he then proclaims that the protagonist just wanted to see everything in the Underground and will eventually return to their malicious ways.

Attacks
As a flower, Flowey uses only two attacks: a five-bullet spread that slightly hone in on the protagonist's SOUL, and a large ring of bullets which surround the SOUL and cannot be dodged. He can speed up the spread though the limits of his attacks and speed are unknown. Getting hit by his five-bullet spread in his first encounter deals 19 damage per bullet. Before his battle as Asriel Dreemurr, the bullets will deal 7 damage until 6 HP where it is 5.

Trivia

 * Flowey and Mettaton represent the two characters with voice clips; Flowey says "That's a wonderful idea!" at the end of the Ruins on a Genocide Route.
 * This phrase is a higher-pitched clip of an old McDonald's commercial originating from the 1960's as seen in this video by Adam Powell.
 * There are other clips within the commercial which have the same, if not exact, voice and sound clips. Examples are times 2:47 and 3:05, where Photoshop Flowey's "hurt" sounds originate.
 * Flowey's laugh is not a new asset and can be recognized in other media such as the PlayStation title Tomba! and the soundtrack The Lordling, also by Toby Fox. The full, unedited laugh can be heard here.
 * If the player attempts to name the fallen child "Flowey," the screen reads "I already CHOSE that name" and prevents the name from being used.
 * In Hard Mode, Flowey appears alongside the Annoying Dog after the protagonist finishes Toriel's boss fight.
 * In a joke thread on Starmen.Net, when Undertale was called "UnderBound 2," it was revealed that Flowey was planned to be the reincarnation of "Face," who was the protagonist of the non-existent EarthBound hack, UnderGround.
 * Flowey's character might be inspired by flowers from EarthBound, which Toby did include in one of his hacks.
 * Flowey has the most battle sprites of any character; he has dozens of expressions that he uses in the battle room.