114.6c If an effect allows a player to “change any targets” of a spell or ability, the process described
in rule 114.6a is followed, except that any number of those targets may be changed (rather than
all of them or none of them).
114.6d If an effect allows a player to “choose new targets” for a spell or ability, the player may
leave any number of the targets unchanged, even if those targets would be illegal. If the player
chooses to change some or all of the targets, the new targets must be legal and must not cause
any unchanged targets to become illegal.
Edited Callum Milne (Oct. 2, 2014 03:43:45 PM)