Argent Whisperblade

Haste, Deathtouch
Whenever Argent Whisperblade becomes blocked, you may exile it and return it to the battlefield tapped at the beginning of the next end step. If you do, place a -1/-1 counter on the blocking creature.
Swift as a river, silent as a breeze. If you see one, it is only because they allow it. If you catch one, your life is forfeit.