If an effect would add mana represented by one or more snow mana symbols to a player’s mana pool, that much colorless mana is added to that player’s mana pool.
May 3, 2019 · War of the Spark
To “tap [a permanent] for mana” is to activate a mana ability of that permanent that includes the {T} symbol in its activation cost. See rule 605, “Mana Abilities.”
January 25, 2019 · Ravnica Allegiance
To "tap [a permanent] for mana" is to activate a mana ability of that permanent that includes the {T} symbol in its activation cost. See rule 605, "Mana Abilities."
April 27, 2018 · Dominaria
To “tap [a permanent] for mana” is to activate a mana ability of that permanent that includes the {T} symbol in its activation cost. See rule 605, “Mana Abilities.”
January 16, 2016 · Oath of the Gatewatch
To “tap a permanent for mana” is to activate a mana ability of that permanent that includes the {T} symbol in its activation cost. See rule 605, “Mana Abilities.”
February 1, 2014 · Born of the Gods
One card (Drain Power) puts all mana from one player’s mana pool into another player’s mana pool. (Note that these may be the same player.) This empties the former player’s mana pool and causes the mana emptied this way to be put into the latter player’s mana pool. Which permanents, spells, and/or abilities produced that mana are unchanged, as are any restrictions or additional effects associated with any of that mana.
September 30, 2011 · Innistrad
One card (Drain Power) puts all mana from one player's mana pool into another player's mana pool. (Note that these may be the same player.) This empties the former player's mana pool and causes the mana emptied this way to be put into the latter player's mana pool. Which permanents, spells, and/or abilities produced that mana are unchanged, as are any restrictions or additional effects associated with any of that mana.
June 17, 2011 · Commander 2011
One card (Drain Power) puts all mana from one player’s mana pool into another player’s mana
May 1, 2011 · New Phyrexia
One card (Drain Power) puts all mana from one player's mana pool into another player's mana pool. (Note that these may be the same player.) This empties the former player's mana pool and causes the mana emptied this way to be put into the latter player's mana pool. Which permanents, spells, and/or abilities produced that mana are unchanged, as are any restrictions or additional effects associated with any of that mana.