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Ever played a game of Magic where it feels like the other player is doing the same thing over and over, and none of it is nice to you? Retrace is the kind of mechanic that makes games feel like that - which is why it's been rated a 7 of 10 on the Storm Scale.
Talk more about this
Retrace is a keyword ability put on spells starting during Eventide. The only spells which have it originally are Instants and Sorceries, though other cards later give it to other card types (we'll get there).
The gist is this: you may cast a card with Retrace from your Graveyard by paying its costs, acknowledging all timing restrictions (you can't cast a Sorcery during someone else's turn, for example), and discarding a Land card in addition to all other costs. As long as you can meet those requirements, you can cast the spell again.
The big part about this for modern Magic players is what doesn't happen - the card with Retrace doesn't Exile itself. That means it just stays there... in the 'yard... able to be cast again and again, as long as you have Lands to discard.
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Build your deck right, and you can keep people off cards with Raven's Crime or kill all their Creatures with Flame Jab. More mana? Syphon Life can kill someone. Waves of Aggression can give you unlimited Combat steps. Maybe with a bunch of 5/5 Flying Elemental Tokens from Call the Skybreaker.
Okay, we get it
The reason it's a 7 on the storm scale is because it creates too much similar gameplay. I personally play a 60-card deck which uses Raven's Crime to deny my opponent a Hand very effectively. In fact, Jump-Start, a much newer mechanic, is a spell which does Exile the original spell on recast, so Wizards sometimes allows for much stronger effects because it can only be done one extra time.
Anything else?
Yup. There are three cards which grant Retrace to spells which don't have it built in - Deeproot Historian, Six, and Wrenn and Six
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Because of Kindred Sorceries existing from back in the day, Deeproot Historian actually can make some Kindred spells have Retrace in addition to Merfolk and Druid permanents. Six, of course, gives Retrace to every nonland Permanent, which is pretty darn powerful. And Wrenn and Six's Emblem can get silly with the right build.
Also, there are a couple of important rulings about Retrace that matter. When you cast a card with Retrace from your Graveyard, you're casting it from the Graveyard, not your Hand (so Phage, the Untouchable would kill you immediately, for example). You must pay all associated costs to cast the card and discard a Land card to cast a spell with Retrace. If a spell with Retrace is countered, it still goes back to the Graveyard... where it may be cast with Retrace again. And finally, if you cast an Instant or Sorcery with Retrace from your Hand and it resolves, it returns to your Graveyard and you may cast it again immediately for its Retrace cost before anyone may remove it from your Graveyard. You retain priority, so you can cast it right then no problem. Note this is only true with non-permanents. A permanent granted Retrace will be on your Battlefield.
Now get out there and cast some stuff again. And again. And again.
Thanks for reading.
