As each step or phase ends, any unspent mana left in a player’s mana pool empties. See rule 500.5.
November 8, 2024 · Foundations
When each step or phase ends, any unused mana left in a player’s mana pool empties. See rule 500.4.
October 7, 2022 · Unfinity
Immediately after the cleanup step begins, if the active player’s hand contains more cards than their maximum hand size (normally seven), they discard enough cards to reduce their hand size to that number. See rule 514.1.
November 19, 2021 · Innistrad: Crimson Vow
Immediately after the active player has discarded cards (if necessary) during the cleanup step, all damage is removed from permanents and all “until end of turn” and “this turn” effects end. These actions happen simultaneously. See rule 514.2.
May 3, 2019 · War of the Spark
When each step or phase ends, any unused mana left in a player’s mana pool empties. See rule 500.4.
January 25, 2019 · Ravnica Allegiance
When each step or phase ends, any unused mana left in a player's mana pool empties. See rule 500.4.
April 27, 2018 · Dominaria
When each step or phase ends, any unused mana left in a player’s mana pool empties. See rule 500.4.