Spark Trigger

As an additional cost, Spark Trigger costs one
mana of target creature's color.
Target legendary creature becomes a planeswalker
with loyalty equal to its converted mana cost and
"+1 Draw a card, -3 Destroy target creature or planeswalker, and -8 You get an emblem with 'Whenever a creature enters the battlefield, create
a copy of it" and "Whenever a player casts a spell,
you may copy it and choose new targets for the
copy.'" It's still a creature.