Karna, Hero of Charity

First Strike, Trample, Ward {2}
Outlast {w} ({w}, {t}: Put a +1/+1 counter on this
creature. Outlast only as a sorcery.)
Whenever this creature is dealt damage, prevent all
but 1 of that damage.
If Karna, Hero of Charity has power 10 or greater,
pay {r/w}, if you do, exile it then return it to the battlefield transformed at the beginning of your
next upkeep. Activate only as a sorcery.