Hash-slinging Stasher

The first time you cast a non-creature spell
each turn, stash a card from the top of your
library under Hash-slinging Stasher.
{b}{t}, sacrifice Hash-slinging Stasher, target
creature gets -X/-X until end of turn where X
is the number of cards that were stashed under
Hash-slinging Stasher.
When Hash-slinging Stasher dies, shuffle all
cards stashed under it into your library.