Koragun, Storm's Fist

{2}{r}: Koragun gains double strike until end of
turn.
{3}{u}: Whenever Koragun takes damage, the
damage instead becomes +0/+1 counters.
+0/+1 counters become +1/+0 counters at the
start of your combat phase. Remove these
counters at the end of the phase if Koragun dealt damage to a creature or player.