High-Five Ghost

High-Five Ghost, also nicknamed High-Five', 'HFG', or even just 'Fives (by Muscle Man) is a ghost who works alongside Mordecai and Rigby as a groundskeeper at The Park . 

Appearance
High-Five Ghost ( Or "Fives", as Muscle Man calls him) is a small, pale ghost. He is semi-transparent as you can see through him, but not completely through. He has basic features, eyes and a mouth and also has one hand sticking out of his head. It was revealed in " Go Viral " that High-Five Ghost has four extra arms, or it is possible that he can spontaneously generate any number of arms that he wants.

Muscle Man
He and Muscle Man seem to be best friends, since they are always assigned jobs together. When Muscle Man is in a frame, it is to be assumed that "Fives" is along with him. The two are inseparable, just like Mordecai and Rigby. When he appears he is always with High Five Ghost. Similar to how Benson never gets mad at Mordecai alone, HFG never makes fun of Mordecai or Rigby by himself (always with Muscle Man when this happens).

Other Employees
High-Five Ghost does not seem to communicate with the workers at all. He usually remains silent, but does obey orders. But after being "unjinxed" by Rigby in " Jinx " he seems to communicate with Mordecai, Benson, Skips, Pops, & Rigby more often.

Family
In the episode, " See You There ", it is revealed that High-Five Ghost has a brother (presumably older) whose name is Low-Five Ghost. Low-Five Ghost looks almost identical to his brother, except that LFG has a bit of scruff where his "chin" would be, and wears teal sunglasses. His personality is that of a wild teenager. Low-Five Ghost has the power to turn non-ghosts into ghosts. However, Low-Five states that he doesn't know how to revert transformed people back into their original, solid state. In " See You There ", HFG's father is also introduced. He remains unnamed except for "Dad" to High-Fives and Low-Five. Their father is also the only one in the Ghost family who knows how to change people from ghosts back into their normal form.
 * Low-Five Ghost
 * High-Five Ghost's Father

Skull Punch
Skull Punch are his enemies. When he and Muscle Man steal his RV they fight.

Scott D.
Scott D. is in charge of getting people to go to the Crash Pit when Muscle Man and High Five Ghost find a car to drive into it.

The Night Owl
The Night owl is a game show host who imprisoned him, Mordecai, Rigby and Muscle Man.

Nicknames

 * Five
 * Fives
 * High-Five
 * High-Fives
 * HFG

Skills and Abilities

 * Undead - Even though it is unknown if he was born alive, High-Five is shown to be a ghost and be living and interacting with others.
 * Strong - High-Five Ghost is shown fighting Muscle Man, Mordecai, and Rigby in The Night Owl and acomplishes on hitting Rigby in the groin.
 * Musical - In This is my Jam, it is shown that High-Five Ghost can play the trumpet, even thought Muscleman blows into the mouth piece.
 * Silent, But Loud Laughs - Even though High-Five is usually silent, he has a very loud laugh, which can be proven in  The Night Owl . He can be shown to be a bit cowardly or confused in some levels.
 * Float - High-Five Ghost can float instead of walk and never gets tired of doing it.

Trivia

 * Despite his name, High-Five Ghost is shown to only have four fingers.﻿ Though, his four other hands have five fingers.
 * Most of the time he is never heard because when he speaks Muscle Man talks over him.
 * He and Muscle Man can be seen with the crowd of people in the Pilot episode watching Mordecai and Rigby playing Rock, Paper, Scissors.
 * When Muscle Man is fired in Don, High-Five Ghost goes with Muscle Man, even though High-Five is not fired.
 * It is unsure if he's as arrogant as Muscle Man, although he does seem to agree with the insults Muscle Man calls out to Mordecai and Rigby.
 * High-Five Ghost's nickname is Fives when Muscle Man and him flee after Muscle Man thinks that a "bucket with wheels" stole Rigby's voice in the episode Rigby's Body.
 * High-Five Ghost wears a four fingered spiked brass knuckle when Rigby's consciousness was emptied into the garbage truck.
 * In Rigby's Body, we finally hear him speak when he says to Rigby "What are you?". In the episode Just Set Up The Chairs he can be heard saying "Yes! Uh!" with Muscle Man, though this is barely heard.
 * High-Five Ghost is almost always smiling.
 * High-Five Ghost first frowns when he carries Rigby down from the roof in Death Punchies.
 * High-Five Ghost is a ghost, but it is not explained who he is the deceased form of.
 * In the episode My Mom, High-Five Ghost actually has three arms instead of one located on top of his head. His other two arms are on the sides.
 * High-Five's hand on his hand looks like a fork, while his other two hands that come out of the side of him have 5 fingers and actually look like human-hands.
 * In Just Set Up The Chairs, it is the first time High-Five smiles without his mouth open. Second is Don. (Pictured in the gallery)
 * Even though it is shown Fives has four other hands, he often does more stuff with his top hand on his head.
 * It is shown that Muscle Man's Uncle John taught High-Five how to fix the engine in the golf-cart to make it go speeding fast. Though, Muscle Man probably was lying, because Fives high-fived him afterwards. Though it's possible that he was saying it was cool that his Uncle John taught him.
 * It's possible that High-Five is also hurt when someone says that Muscle Man doesn't say his jokes right.
 * High-Five Ghost is a great bowler as proven in My Mom.
 * High-Five Ghost holds up the rock sign many times in My Mom.
 * High-Five Ghost likes to annoy Benson, along with Muscle Man. This is proven in Don.
 * High-Five Ghost is a fan of Fist Pump. This is proven in Caffeinated Concert Tickets.
 * In Death Punchies, it's unknown why Rigby punches him because he is not shown to have beaten Rigby at Punchies. Also, he is shown to be hit but he is not shown with Muscle Man smashed into the building, which may mean his is weightless and had floated into the air like a balloon.
 * When High-Five shouts "OOOOOHHHH!" with Muscle Man and the Taco'Worker, he is not heard.
 * High Five Ghost has many nicknames, including High-Five, High-Fives, Fives, HFG, and Five.
 * In the episode Benson Be Gone, High-Five turns to normal because he didn't do what Susan says and then drinks a whole can of soda.
 * This Is My Jam marks the biggest expression on High-Five's face and also marks the only time he frowns with his mouth open.
 * High-Five Ghost is voiced by JG Quintel, but is voiced by Jeff Bennett in early episodes.
 * High-Five Ghost's facial expressions resemble those of the faces of Comedy and Tragedy that are in plays and theaters. Both of these expressions are used in Don.
 * In Jinx, he was unaffected by the Jinx monster's scratch probably due to intangibility, though he didn't use it when punched by Muscle Man.
 * In See You There, Low-Five, his brother says that ghosts can't be hurt but he is punched multiple times by MM in Jinx and hurt and pummeled by the Hammer in "Rage Against the TV".
 * It is possible but highly unlikely that he could have been born a ghost.
 * High-Five Ghost sounds eldery when he says "Uh-huh" in Rage Against the TV.
 * The closed captioning and credits incorrectly call him "Hi Five Ghost".
 * The credits credited J.G. Quintel, Mordecai's voice actor, for voicing him in "Just Set Up The Chairs" and "Rigby's Body" even though Jeff Bennett voiced him. Though, Quintel voices him in season two and onward.
 * Interestingly, Mordecai and High-Five are frozen next to each other in The Night Owl.
 * With the exception of High-Five Ghost, all of the main characters have been antagonists at least once (although the real Pops isn't an antagonist, Mordecai 's memory of Pops is).
 * High-Five Ghost resembles his father and brother.
 * In the episode Go Viral, it is revealed that High-Five Ghost has five arms: the one on his head and another four which he keeps hidden.
 * He thinks the internet sensation Wedgie Ninja is funny.
 * Hi-Five Ghost has the most family members actually seen in the series (Being his dad and brother; both in "See You There"). Rigby, Muscle Man, and Pops having one (Pops having his father, Mr. Maellard and Rigby having his brother, Don, and Muscle Man having his brother John) and Mordecai, Skips, and Benson having none so far)