Explain/Spike
Spike is an enemy in the Super Mario franchise of games. He is also a commentator for the Wiki Camp 2, forming a duo with Michael Bloomberg and Vriska Serket.
Outside the Wiki Camp 2
Spike as an enemy was introduced in Super Mario Bros. 3, but the design used on the wiki camp wasn't used until the New Super Mario Bros. line of games. It was here he got his signature blue hair as well, as games before then depicted him as bald. Following this reintroduction, he would appear in many side games, such as Mario Tennis Aces and Paper Mario Sticker Star, further cementing him as a main-stay in Bowser's entourage of goons.
Despite appearing in so many games, his dialogue has been scarce and far between, with some of the only known dialogue coming from Paper Mario: the Origami King as part of the Canned Food Trio. As a result, Wiki Campers have had to look elsewhere for what to base his dialogue on. Looking online, one Wiki Camper found a meme depicting the enemy standing towards the camera, with large bold text saying "DUDE" in all caps. This image would be the basis of Spike's Wiki Camp personality and typing style, right down to the specific render used for his Dia box.
Inside the Wiki Camp 2
In the Wiki Camp 2 canon, Spike is one of the moderators of the camp, along with his good friend Michael Bloomberg and benefactor Vriska Serket. He also comments on happenings of the camp, such as results starting or a new challenge beginning. These can be seen on the main page, which gets updated when a new challenge starts and when challenge judging ends.
Along with being a moderator, he and Bloomberg are also the lead investigators on the disappearance of Versus, a member of the band and competitor Playlist. As a result, they have interviewed a couple different characters, such as Jurta and Big Boy's driver. These interviews can be found in the category Story posts, and a good starting point would be Diary's, even though most of them are episodic in nature. This is due to how Diary's interview starts a running gag of Spike and Mike having a Super Smash Bros. feud, which would be lost if one didn't start there.
During the edit war, Spike was temporarily his bluer cousin, Stone Spike. His partner in crime, Michael Bloomberg, was also temporarily swapped, with him trading places with TheDeviousSeal32. This would be reverted by Copper Pepper some time after the edit war ended, with the power of CSS Magic.