Ditto, Learning Mage

Changeling (This creature is every creature type.)
Discard a creature card: Ditto, Learning Mage
gains all keywords from the discarded creature
card until end of turn.
{w}{u}{b}{r}{g}: Target opponent reveals their hand,
you may choose and instant or sorcery. You may
cast a copy of that spell without paying its mana
cost until the end of the turn.