Comprehensive Rules
306.4
Previously, planeswalkers were subject to a âplaneswalker uniqueness ruleâ that stopped a player from controlling two planeswalkers of the same planeswalker type. This rule has been removed and planeswalker cards printed before this change have received errata in the Oracle card reference to have the legendary supertype. Like other legendary permanents, they are subject to the âlegend ruleâ (see rule 704.5j).