Finn

Finn, also known as Pen in the original short, is a twelve-year-old boy who goes on adventures with his best friend, Jake. He wears his self-proclaimed "awesome" white hat everywhere. He often shouts random mathematical terms, such as "Algebraic!," despite the fact that in Slumber Party Panic, Princess Bubblegum revealed that Finn is terrible at mathematics. In the Animated Short, it was shown that Finn has feelings for Princess Bubblegum.

Appearance
Finn wears a white hat that covers his entire head, but leaves an opening for his face. He wears dark blue shorts and a plain blue shirt. He carries a green backpack on his back, and wears black shoes. When going to the Ice Kingdom he wears a brown turtleneck. It has also been noticed that Finn has messed up teeth. He may be 5 feet tall or taller.

Personality
Finn is a brave adventurer. He only fights creatures that are evil. In the episode The Enchiridion, he slays Heart Beast, but could not kill the neutral, harmless Ant. He blushes at a compliment Jake makes during the same episode. His face gets red when he is ashamed at himself or really furious. He often loses his temper when other people makes things harder for him and get in his way, such as Lumpy Space Princess and Tree Trunks. However, he apologizes to them during the same episode that he gets angry at them, which shows that he can be caring. Several girls flirt with him or try to kiss him, including Tree Trunks, Marceline, Slime Princess, Hot Dog Princess, and even a couple more. The only one that he harbors a deep crush on though is Princess Bubblegum.

Abilities
Finn is proficent in Kung-Fu, as seen in the animated short. He is unable to swim, as shown in Ocean of Fear. He is able to do the science dance, which was introduced in Ricardio the Heart Guy. Finn also has the ability to make his voice autotuned, because in The Jiggler, it was revealed that he swallowed a small computer.

History
As mentioned in Memories of Boom Boom Mountain, the reason Finn is a hero is because one day when he was a baby he took a "boom boom" on a leaf and fell in it. Ever since then, he cries when he takes one. It is unknown who gave birth to him. How he met Jake is also unknown.

Enemies
Some of Finn's enemies are:
 * Ice King
 * Ricardio
 * Ogre
 * Grim Reaper (Enchiridion)
 * Marceline, although occasionally friends

Finn and Jake
Finn and Jake are best friends and will go out of each others way to protect each other. Finn becomes visibly angry whenever Jake is hurt or presumably dead. This relationship existed from the start of the series.

Finn and Princess Bubblegum
Finn has a crush on Princess Bubblegum, although he has not shared his feelings. He became jealous when Ricardio kept flirting with her, however he denied it furiously.

Quotes
"Yeah, there's a big sleeping lava man in our front yard... and he is SO hot. Wait, wait, no, I take that back. I mean, not like sexy hot..."

"He's not my dog... he's my friend!"

"My hat... is... AAAWESOOOME!"

"I'll slay anything that's evil, that's my deal!"

"Get ready for an uppercut, you dog!"

"I feel radder, faster... more adequate!"

"Baby, I know what you crave."

"Do you think I have the goods Bubblegum, because I am into this stuff."

"Momma's spposed to love babys!'

"She smells like old hot dog water."

Trivia

 * In the pilot episode/short Finn was named Pen, a name he got from the show's director and producer, Pendleton Ward.
 * In the pilot, Finn is voiced by Zack Shada. However, in the series, he is voiced by Zack's little brother, Jeremy Shada.
 * Even though Finn can't swim in the episode Ocean of Fear, he was seen swimming in a lake in the episode Business Time.
 * Jake says Finn cries when he takes a Number 2.
 * Finn's hat has a small resembelence of Bueno the Bear from "Barrista" (a short from Pendleton Ward).