Mirrorshard Crystalwyrm

Flying, trample
Mirrorshard Crystalwyrm enters the battlefield
with X +1/+1 counters on it.
Whenever Mirrorshard Crystalwyrm would be
destroyed, instead remove a +1/+1 counter from
it and create a token copy of another permanent
you control, except it's a 0/1 artifact creature in
addition to its other types and it has defender.