Timeshifted cards make up a 121-card subset comprised entirely of pre-Mirrodin reprints, tying in with the set's theme of revisiting the past. Each card in the subset features the old 7th Edition card frame and has a new purple expansion symbol to denote their unique rarity. One timeshifted card appears in every Time Spiral booster pack, making the cards roughly 50% as rare as rare cards, which also appear once per pack but comprise of only 80 cards. However, in the Time Spiral preconstructed decks, timeshifted cards are treated as though they had their original rarity, as each deck features several of the timeshifted cards that were originally common, including multiples of the same card.
Timeshifted cards are treated as a part of Time Spiral block, thus it is legal in any format that uses Time Spiral's cards (Standard, Extended, Block Constructed, Modern).