Whenever you cast a red spell, untap Chandra, Fire of Kaladesh.
T: Chandra, Fire of Kaladesh deals 1 damage to target player. If Chandra has dealt 3 or more damage this turn, exile her, then return her to the battlefield transformed under her owner's control.
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Chandra, Roaring Flame
[+1]: Chandra, Roaring Flame deals 2 damage to target player.
[-2]: Chandra, Roaring Flame deals 2 damage to target creature.
[-7]: Chandra, Roaring Flame deals 6 damage to each opponent. Each player dealt damage this way gets an emblem with "At the beginning of your upkeep, this emblem deals 3 damage to you."

NOTE: Stock image, not actual card.