This will be a quickie! As you know by now, I'm a fan of Burn, Discard, and Mill decks. If possible, I would have multiple variants of each, assuming I had the cards to build the decks without having to swap cards between them. Burn decks were the easiest for me to accomplish that task.
Fire & Ice (Apocalypse) worked its way into one of my red/blue Burn variants. I can't remember all of the pieces, but many of the blue and artifact spells would store (or steal) mana, which could then be used to cast large damage dealing burn spells. I was never able to fine-tune the deck, but it still won me a handful of games.
This card was unique, because it was the first introduction of Split cards. Essentially they are two cards built into one and you can decide which "card/spell" you want to cast. Each has its own name, casting cost, effect, etc etc. This allows for more versatility in games, where you can cast the half that better suits your current strategic needs.
There were a handful of these in the Apocalypse set and were even brought back in a future expansion, but Fire & Ice was always my go to Split card! Plus, part of the draw may be based on an animated movie I like of the same name. They aren't worth much, but I keep my foils in a toploader nonetheless.
Have you ever played with Fire & Ice in a deck? What about Split cards in general? If so, do you have a favorite? Have you ever built a red/blue deck? If so, what are some staples you have in it?