Modern Pyromancer deck
Pyromancer is a blue and red combo deck and comes in two variants. Both variants try to abuse a red enchantment with the word "Pyromancer" in the name, either Pyromancer's Swath or Pyromancer Ascension.
The Swath based deck attempts to put together a critical mass of spells and mana in a single turn, using Rite of Flame, Desperate Ritual, and Seething Song. Using this, Pyromancer's Swath is cast followed by a Grapeshot, with the Grapeshot copied through storm and its damage output enhanced by Swath. The blue component of the deck is primarily card filters to assemble the critical mass and find Swath and Grapeshot.
The Ascension based deck uses the blue cards to find copies of cards already in the graveyard and power up the Ascension. The Ascension in turn then powers up those search cards. This culminates in a game-ending string of copied Lightning Bolts, a stormed Grapeshot, or a Banefire.