Disclaimer: While not a WIP, this can and will be updated if new ideas or formats are introduced. This is a complete character, just evolving over time.

This article, Defense Revenge, is owned by Kung Fu Kirbeh. Please do not edit this article without their explicit permission.


Defense Revenge was born to a few Fire Elementals on the edge of the Underground and Richten territory. He lived a normal life, interested in the arts of battle and cooking. When he came of age, he started wandering around on his own, eventually becoming lost in Richt territory. He managed to find his way out, but it oddly made him want to see the world. He trained in the arts of magic and combat for a year before leaving his house and going into the normal Underground, planning for the future. He met friends and foes, Humans and Monsters, before eventually settling down in Snowdin and getting a job at MTT Resort. He worked there for about a month before Mettaton hired Burgerpants instead. He now works at Grillby's, where he can continue his culinary training. He wishes to lead a somewhat peaceful life, but it seems like ever since the first human fell, that is the farthest thing from his mind.

Defense is easygoing and talkative, and very capable in day-to-day life and in combat. He is a Fire Elemental with golden fire, a black formal shirt with gold vest, and formal pants with golden fire sewn on the bottoms of the legs, as well as rims on a pair of glasses he found, with no lenses. As of his recent sword training, he now carries a rapier in a holster on his back, similar to Future Trunks.

He lives about a mile away from Grillby's, in a house made of cobblestone and other fireproof materials. It's a cozy place, and big enough to entertain guests if needed.

Defense is possibly stronger than other Fire Elementals, and knows a variety of attacks from anime/games he occasionally sees/plays such as the Psycho Crusher and the Omega Eraser.

Defense has met Gavin previously, by chance. They immediately hit it off, and have been great friends since.

Defense has picked up a steady job at Grillby's, but most of his shifts happen while the human is out of the restaurant.

Defense can appear in 2 of the 3 runs; with different intensities with each. In Genocide, You will have to fight him after killing Gavin. This is by far the most brutal version of the fight, as he will constantly test your skill, and will not be killed in one hit, unlike Sans. In Pacifist, he will appear around Hotland as an alternate boss if you buy the Spider Donut before Muffet's boss fight for 9999 gold. He will challenge you to a fight, and will flee after 30 turns. If you defeat him, it will not count for your kill count, and he will refund your money, and warn you not to Genocide.

He also has a Nostalgia Fight in the Pacifist run if you visit Grillby's on the walk back. He will use only attacks from bosses and enemies from Undertale. The background will also be the rainbow background of the Asriel fight.



Frisk: Pacifist only.

Gavin: A friend from another time. He doesn't like to talk about it, but he still communicates with him often.

Sans: They talk a lot when Sans visits Grillby's during his shift. Defense considers them friends.

Grillby: His employer and close friend.

Tem Merchant: He buys all of his ingredients from the Merchant, and hopes that it can achieve its dreams.

Platinum Alucard: Often helps her and her family out, and asks for help in return. Like Sans, he considers them friends.


Frisk: Neutral only.

Burgerpants: Met and talked with him on a few occasions when he visited MTT Resort.

Nice Cream Pants: Met him a few times when he wanted some Nice Cream.

Mettaton: He was an intern at MTT Resort, but was replaced with Burgerpants after a month of work. He has since forgiven Mettaton.

Alphys: Anytime he needs science, he visits Alphys. Plus, he gets to watch some DBZ too.

Temmies: Interacts with them on his way to see the merchant.

Bob: His difference from the other Temmies slightly disturbs Defense, but he doesn't think about it.

The Perverted Mind: He's had a run-in, and pities the poor creature.

Joseph Alucard: He helps Platinum a lot, and he has familiarized himself with her brother Joseph.

Emily (Agarif): A frequent visitor to Grillby's while he's on shift. Reason Grillby's sells fries on their regular menu.

Salsa: He used to pity him along with the rest of the CC before it disbanded. Reason Grillby's sells the Ghost Burger, the spiciest food in the Underground and the Land of Richten, on the regular menu.


Frisk: Genocide only.

Condiment Crew He has had to face them a few times when they try to rob Grillby's. His track record is spotty, but he comes out on top if they don't bring Salsa.

Flowey: He hates Flowey with a vengeance, attacking him on sight.

Romantic Relationships

N/A: This flame is an eligible bachelor at the moment...


Pacifist (Muffet)

  • HP: 5000 ATK: 30 DEF: ????

Pacifist (Nostalgic)

  • HP: 6500 ATK: 40 DEF: 40


  • HP: 10000 ATK: 30 DEF: 50


Pacifist: Bribe, Flex, Skip, Bluff

Genocide: Struggle, Plead, Escape, Grin

Nostalgic: Remember, Grin, Cry, Nod


Defense can do a few "unique" things.

  • He has some training in swordplay, especially with rapiers. He created his own fighting style only he knows, which sits somewhere between the styles of Inigo Montoya and Silver Chariot.
  • The ability to "charge" himself by creating plasma from his own flame. This behaves like electricity, with a few buffs and nerfs:
    • Buffs:
      • It can cauterize wounds
      • It can burn enemies much more efficiently
      • Defense can liquefy it, creating basically lava
    • Nerfs:
      • It cannot travel through water or the human body
      • It takes away part of Defense's flame, technically hurting him
      • It has to be used, it can't be discharged like electricity can
      • It cannot electrically charge anything. For example, The plasma cannot restart a car battery.
  • He can regenerate from even an ember if it is hot enough, BUT he can still take physical damage. This is not invincibility. He still takes damage and does not regenerate HP. This is more so insane physical endurance, which allows him to keep fighting, even at low health.
  • His wounds immediately cauterize due to him being made of flame.
  • Since he is made of flames, he casts no shadow, so Shadow Manipulation magic and similar abilities have no effect on him.


Omega Eraser: A circular projectile that does 15 damage. Acts differently each time, and is Green so people can run into it.

Chaotic Flame: A background Effect that makes the Bullet Board an Orange Attack for 4 turns. Every hit does 2 Damage.

Line Bomber: Turns the Soul purple for 1 turn and sends bombs down the lines. Each bomb is slow but does 15 damage.

Psycho Crusher I: Blue Attack that takes up entire Bullet Board. Does 20 Damage.

Psycho Crusher II: Orange Attacks that go up and down the Bullet Board without warning. does 10 Damage.

Psycho Crusher III: White attacks that go in many directions in the Bullet Board. Each hit does 5 damage.

Whack I: Blue Attack that sweeps the Bullet Board. Does 30 Damage.

Whack II: Orange Attack that sweeps the Bullet Board and bounces twice. Does 20 Damage per hit.

Assault Rain: Rain of Orange, Blue, White, and Green attacks. Does/Heals 5 damage per hit. Genocide version does not heal.

Rose Toss I: Throws a Rose which can be Orange or Blue and takes up half of the Bullet Board. Does 30 Damage.

Rose Toss II: Throws multiple White roses which linger and spin on the Bullet Board. Does 10 Damage per Rose.

Rose Toss III: Throws one incredibly small rose which shrinks the Bullet Box for one turn if it hits. Can be used befre or after another attack.

Flash: Orange Attack that lights up in a circle of 3 different sizes. does 30 damage.

Flare Kick: Orange Attack that slashes through the middle, taking up 1/3 of the Bullet Board. Probably used after Flash. Does 30 damage.

Mine Trail: Orange and Blue attacks that pop up randomly. Sometimes used after Flash. Each explosion does 15 damage.

Slice Kick: White attack that slices through Bullet Board and lingers for a few seconds. Used after Mine Trail. Does 40 damage if hit, does 20 damage if you run into it after the fact (like an idiot, I might add. :p)

Stardust Breaker: Ya know Asriel's Star Breaker or something like that? Yeah, basically what it is. 20 Damage per star.

Reppuken: Fires shots of different colors, sizes, and speeds along the sides of the Bullet Board, occasionally cutting through the center. Small does 15 damage, Medium does 25 Damage, Large does 35 damage.

Double Reppuken: Fires a large shot through the center that is Blue, Orange or White, usually following Reppuken. Will not be used during Chaotic Flame. Does 50 Damage.

Destructo-Disc: Fires two circles, one Orange, one Blue, that move around the Bullet Board. 25 Damage per circle.

God Press: A White line moves from one side of the Bullet Box to the other, and then turns Orange at the opposite end, then turns White and returns to the other side of the Box.

"I'll heal you, and then BEAT YOUR ASS": A large, obvious, dodgeable Green heart shape slowly moves down the center of the Bullet Box. If the SOUL touches the Green, Defense will launch an unblockable attack which sends the player down to 1 HP, no matter how much they have left. #NoobKiller

(In fights between 2 OCs, "I'll heal you, and then BEAT YOUR ASS" is power scaled down, both with the heal and the damage. Depends on the DEF of the OC, among other things.)


Defense will usually use weaker moves, every so often using a more dangerous move. He will often mix Chaotic Flame and other moves, represented by an orange Bullet Board.

There is a 1% chance in the Post-Muffet fight that, when flexing, Aaron will come and challenge you to a flexing contest, ending the fight early.

In his Pacifist fights, Defense will show you a number before a numbered attack, similar to a pitcher in baseball. He will show the same numbers to show the player how many moves he will use in the Flash chain, but it will be on his other hand.

The behaviors of Omega Eraser will be shown by the hand Defense tosses it with. If he tosses it with his left, it will act White. If he does it with his right, it will act Blue.

To satisfy Defense, you have to get his health below 50%, then spare him.

Psycho Crusher I and "I'll heal you, and then BEAT YOUR ASS" will not be used in conjunction with any other moves, except with Rose Toss III in Genocide.


Main Theme: Sir Mix-A-Lot-Iron Man

Pacifist (Post-Donut Skip): Pink Floyd-Another Brick In The Wall

Pacifist (Post-Asriel): Queen-We Are The Champions

Genocide: Bo Burnham-Kill Yourself mixed with ASGORE


"Hey, kid. How's it going? Good? Good. You Skipped Muffet! Great Job. I've been hired as a replacement boss. Prepare yourself!" [When you first meet him in Pacifist]

"I cannot let you advance! You killed Sans and Gavin, but I still have to try!" [Before Genocide Fight]

"Hey Kid- Where are you? And why do I hear a keyboard?" [If you call while in Gavin's house]

"LEEEEEEEEEEEEEEEEEEGS!" [If you call directly after the Mettaton Fight]

"Sup. I suppose you are walking back for a trip through memory lane? Let me help with that." [Before Nostalgic fight]

"You Can Win! You Feel Great! YOU! CAN! DO! THIS!" [If you call before Photoshop Flowey or Asriel fight for the 1st 3 times]

"Have we done this before?" [Before Photoshop Flowey or Asriel fight, 4th+time]

"Not half bad, kid. You did well." [After defeated, Post-Muffet]

"A secret room? Careful, this might be the work of an enemy stand!" [If you call while in the Gaster room, Toby room, or a debug room]

"I know what you're thinking. Sans is not Ness. I checked." [If you call while in Sans's shed]

"Oh boy. Better be careful, ASGORE is a meanie. Wait, why did I say his name like that?" [If you call before fighting Asgore]

"Seems like there's no one here. I wonder what could happen if you came here when the sign says?" [If you call in the area where you meet SO SORRY, wrong date and time]

"zzzzZZZzzzz... Ugh-Huh? Why are you up so late?" [If you call him in any other place not mentioned above between 11 PM and 3 AM]

"Friday? FRIDAY? I gotta get to Alphys's ASAP! It's Jojo Friday!" [If you call on a Friday, with none of the above conditions met]

Flavor Text


Defense challenges you! [Pacifist]

Defense stands in your way. Strike him down. [Genocide]

Flavor Text

Defense stands his ground. [Grin]

Defense blasts you back in his way. [Escape]

Defense ignores your cries. [Plead]

Defense is unphased. [Struggle]

Defense reluctantly declines. [Bribe]

Defense reads your bluff unflinchingly. [Bluff]

Somehow, Mettaton's ratings boost as Defense facepalms. [Flex]

You offer to skip your turn. Defense insists that you go ahead. [Skip]

I think we're done here. [Flex, Aaron appears]

Defense taps his foot impatiently. [Pacifist Idle]

Defense snorts angrily. [Genocide Idle]

AU Forms

Underswap: A human who can use "Shortcuts" and the "Mimic" technique. Has the same role as normal.

Underfell: A silver Grillby race who works for the Royal Guard. Wears a Red and Black tux and tries to assault the player on multiple occasions.

Undersail: Lives on a deserted island in the center of the sea, alone. A hidden shopkeeper who does not fight you, but sells helpful items for a good price.

Error!tale: Xeno!Trunks like character with long black coat and sword; Self-Proclaimed Enemy of Error!Sans.

UnderNet: Username is DefRevenge24601.


There are rumors saying that Defense is Grillby's son from the future. These have been confirmed false.

If you use the name Defense in the name selection screen, It will say "Who would be stupid enough to name themselves after a Stat? Oh wait..." and not let you choose the name.

If you use the name DEF in the name selection screen, it will say "Okay, fine. But I won't like it."

In the True Pacifist ending, Defense ends up managing the new Grillby's on the surface.

If he was satisfied, he will end up becoming a famous TV chef as well as his own head bodyguard.

Defense's design is mildly influenced by Kyo Kusanagi of the King of Fighters series. His new design was inspired by Jin Kazama of the Tekken series and Shizuo Heiwajima of Durarara! and it's sequels.

Defense has an odd fondness for Devilman, Gintama, Haruhi Suzimya, and Jojo, and will often pester Alphys about watching it together.

Defense can be seen working at Grillby's in a few situations:

A. The walk back through the Underground in True Pacifist, which is also the trigger for the Nostalgia fight.

B. If Gavin is at Grillby's at the time.

C. If you reset in the small span of time between killing Sans and Asgore in Genocide, then play Pacifist until Sans brings you to Grillby's, Defense will be working side by side with Grillby.

D. If you skipped Muffet's fight and beat him in Pacifist, he will show up as a trainee.

Frisk's relationship descriptions being so vague is the fact that he could meet them in different points in each run.

The Situational Rainbow is inspired by a similar feature in the game Super Princess Peach.

Defense's favorite video games are Capcom vs SNK 2: Mark of the Millennium, Kingdom Hearts II, and Crash Bandicoot: Twinsanity.

Due to the nature of his fight, Defense cannot be betrayed.

Defense lost the Featured Article voting of May 2017 to Magical Sabrina, by 2 votes.


Obviously, thanks to Toby Fox for making Undertale.

Thanks to all of the mods and other users for helping me along!

And thanks to ComicsansXD For introducing me to this wiki.

Characters mentioned owned by ComicsansXD, Jedha,The Savior Of The Demons, FalcoLombardi, ZeroByteS, Dove of Death, Person-Man-Thing Official, Koolevan890, and Golden Forge.


Nothing to see here. [Yet.] Goodbye!