Frostmourne

Equipped creature gets +2/+2, deathtouch,
menace, and gains, "Whenever equipped creature
deals combat damage to a player, that player puts
the top twenty cards from the top of his or her
library into his or graveyard. You may cast any
number of creature cards put into the graveyard
this way onto the battlefield under your control."
Equip: {2}{u/b}{u/b}
"Frostmourne hungers." -Death Knight Arthus