For instance, if a player tapped a Swamp to cast Dark Ritual, adding to their mana pool, then cast Erg Raiders (which costs ), and then let the phase in which Erg Raiders was cast end but didn't spend the remaining , that player would lose 1 life from mana burn.
- 300. General (Obsolete)
- 300.3. When a phase ends (but not a step), any unused mana left in a player's mana pool is lost. That player loses 1 life for each one mana lost this way. This is called mana burn. Mana burn is loss of life, not damage, so it can't be prevented or altered by effects that affect damage. This game action doesn't use the stack. (See rule 406, "Mana Abilities.")
Mana burn was almost removed in the Sixth Edition rules update, but Mark Rosewater fought to keep it in. Ten years later, he fought to have it removed. His reasons to remove it were that it would free up design space, do away with a rule that's confusing for new players and that it's a rule that wasn't pulling its weight.
He tried it out in design by having all designers play without mana burn for a month. It hadn't come up in playtests at all during the whole month. The rule requires an unusual set of circumstances: either one has donated mana to an opponent at an inopportune time, or the player has significant amounts of mana producers that generate mana in unusual chunks or phases.
In storylines, mana burn happens when a wizard holds mana and doesn't use it to cast the spell. Such a wizard can seriously suffer from it, be killed, or even be burned to ash if the amount of mana was too big. Some victims of mana burn can also be turned into the Fallen.