Undyne the Undying

If you have 10 or more creature cards in your graveyard give Undyne the Undying indestructible and a -1/-1 counter.
{u/b}{u/b}{x} Give target creature X +1/+1 counters
(only use this ability if Undyne the Undying has indestructible)
You'll destroy them all, Monsters... Humans...
Everyone, won't you? But I WON'T let you do
that.