History of CR 306.9
Every distinct wording since 2010, newest first.
May 3, 2019 · War of the Spark
If a planeswalker’s loyalty is 0, it’s put into its owner’s graveyard. (This is a state-based action. See rule 704.)
January 25, 2019 · Ravnica Allegiance
If a planeswalker's loyalty is 0, it's put into its owner's graveyard. (This is a state-based action. See rule 704.)
February 1, 2014 · Born of the Gods
If a planeswalker’s loyalty is 0, it’s put into its owner’s graveyard. (This is a state-based action. See rule 704.)
September 30, 2011 · Innistrad
If a planeswalker's loyalty is 0, it's put into its owner's graveyard. (This is a state-based action. See rule 704.)
June 17, 2011 · Commander 2011
If a planeswalker’s loyalty is 0, it’s put into its owner’s graveyard. (This is a state-based action.
April 1, 2011 · Duel Decks: Knights vs. Dragons
If a planeswalker's loyalty is 0, it's put into its owner's graveyard. (This is a state-based action. See rule 704.)
February 4, 2011 · Mirrodin Besieged
If a planeswalker’s loyalty is 0, it’s put into its owner’s graveyard. (This is a state-based action. See rule 704.)
October 1, 2010 · Scars of Mirrodin
If a planeswalker’s loyalty is 0, it’s put into its owner’s graveyard. (This is a state-based action.
February 1, 2010 · Worldwake
If a planeswalker's loyalty is 0, it's put into its owner's graveyard. (This is a state-based action. See rule 704.)