Agrogag, the regenerated

whenever Agrogag, the regenerated is killed
by a creature, destroy that creature.
when Agrogag, the regenerated is put into your
graveyard or exile, put it onto the battlefield
tappedwith a +1/+1 counter on it for every time
is has been killed or put into exile.
"you've done it once again, Arthur Dent,
you've killed me again!"