Character: The Trickster/Loki/Gabriel
Actor: Richard Speight, Jr.
First appearance: Tall Tales (Season 2)
Last appearance: Hammer of the Gods (Season 5)
Number of episodes: 4
Species: (Demi-God, Pagan God) Archangel
Powers: Altering reality, Teleportation, Telekinesis, Manipulating time, Fast healing, Super strength, Angelic possession, Invulnerability and Immortality (to a degree)
We are introduced to Gabriel in season 2 as the Trickster. In 'Tall Tales' strange things are happening on campus. A professor gets shoved out of the window, supposedly by a ghost. A research scientist drops his watch into the sewers and gets killed by an alligator trying to reach it. And a frat boy gets abducted by aliens, who probe him and then make him slow dance with them.
Dean and Sam, who are fighting amongst themselves most of the episode, call in the help of Bobby when they reach a dead end. It doesn't take Bobby long to figure out what's behind all this. The fact that all the victims needed to be knocked down from their high horse, is another clue.
Knowing that they are faced with a Trickster, they only need to find out who it is. It isn't too hard to find out that the janitor is the one responsible for the past events.
We don't hear from the Trickster for a while, until he suddenly pops up again in season three. In 'Mystery Spot' Sam gets caught in a time loop. Reliving Tuesday over and over again, his mood continuously sours. The fact that he has to watch Dean die every day doesn't help either. When one of the customers in the local dinner suddenly orders another kind of syrup, the pieces fall in place and Sam confronts the Trickster.
This time Gabriel disappears for a longer time. In season five's 'Changing Channels', he suddenly decides to interfere with the Winchesters' lives again. Trying to teach them a lesson, namely that they have to play their parts in the big plan, he traps them in TV-land. The brothers star in a sitcom, a doctor show, a game show, a procedural cop show, and even a commercial, before they figure out just why this Trickster is so powerful.
This is the episode where Gabriel's true identity is revealed. We also learn more about him, as he tells Dean and Sam his true reason for going into his version of the 'Witness Protection Program'. Gabriel was tired of watching his brothers fight and left. He had been living a good life on Earth, pretending to be something entirely different than what he is, but then Sam and Dean showed up and ruined it for him.
The final episode featuring Gabriel is called 'Hammer of the Gods'. We learn that Gabriel has another hidden identity as the Pagan God, Loki. When Lucifer hops in for a murderous social call, Gabriel stands up to him and gets killed in the process. He had handed a DVD to Dean for safe keeping. On it, he reveals the secret on how to trap Lucifer again.
A tribute to Gabriel: