NOTE: This article is about the incarnation of Riptide from the X-Men film series. The mainstream version can be found here: Riptide.
Riptide is supporting antagonist in X-Men: First Class. He is a member of the Hellfire Club and has the power to spin his body fast enough to create large tornadoes.
In 1962, Riptide was a member of the Hellfire Club. He attacked Division X with Azazel and Sebastian Shaw.
Riptide later joined his teammates to fight against the X-Men. During the Cuban Missile Crisis, while Erik Lehnsherr was magnetically pulling Shaw's submarine out of the water, Riptide created a tornado, causing both the X-Jet and the submarine to crash on the beach. He was knocked out when Erik pulls a piece of the submarine hull out on top of him. After Sebastian Shaw is killed, Riptide joins Magneto's new Brotherhood of Mutants, along with Mystique, Angel, and Azazel.
X-Men: Days of Future Past
Though Riptide was not mentioned in X-Men: Days of Future Past, it can be assumed that he died while being experimented on by Bolivar Trask, though there is a small possibility that he escaped capture at every turn, as little is known about him at all. Either way, this event is what led an angry Mystique to plot to kill Trask, though Xavier soon learns that doing so would only lead the creation of the Sentinels, which would later destroy both mutantkind and mankind in the future. Fortunately, Xavier managed to send Wolverine back in time to convince Mystique out of her vendetta, allowing the authorities to arrest Trask for selling military secret to foreign countries.
Trivia
Riptide is extremely similar to a genderless villain named Arclight, as, apart from a couple of notable physical likenesses, they are a prominent henchman of the main antagonist whose powers generate white energy to devastating effect, yet they have no lines (whereas even Azazel and Quill have dialogue, however minimal). Additionally, they both have six minutes of screen time in First Class and The Last Stand, respectively.