The controller of a mana ability is determined as though it were on the stack. See rule 605, “Mana Abilities.”
July 12, 2019 · Core Set 2020
An emblem is controlled by the player that puts it into the command zone. See rule 114, “Emblems.”
May 3, 2019 · War of the Spark
An emblem is controlled by the player that puts it into the command zone. See rule 113, “Emblems.”
January 25, 2019 · Ravnica Allegiance
An emblem is controlled by the player that puts it into the command zone. See rule 113, "Emblems."
May 1, 2014 · Journey into Nyx
An emblem is controlled by the player that puts it into the command zone. See rule 113, “Emblems.”
February 1, 2012 · Dark Ascension
An emblem is controlled by the player that puts it into the command zone. See rule 113, "Emblems."
September 30, 2011 · Innistrad
In a Planechase game, a face-up plane card is controlled by the player designated as the planar controller. This is usually the active player. See rule 901.6.
July 15, 2011 · Magic 2012
In a Planechase game, a face-up plane card is controlled by the player designated as the
June 17, 2011 · Commander 2011
In a Planar Magic game, a face-up plane card is controlled by the player designated as the
February 4, 2011 · Mirrodin Besieged
In a Planar Magic game, a face-up plane card is controlled by the player designated as the planar controller. This is usually the active player. See rule 901.6.
October 1, 2010 · Scars of Mirrodin
In a Planar Magic game, a face-up plane card is controlled by the player designated as the
February 1, 2010 · Worldwake
In a Planar Magic game, a face-up plane card is controlled by the player designated as the planar controller. This is usually the active player. See rule 901.6.