Sardar, Shadizar Thief

Menace (This creature can’t be blocked except
by two or more creatures.)
Whenever Sardar, Shadizar Thief deals combat
damage to an opponent, you may take control
of target artifact that opponent controls with
converted mana cost less than or equal to the
number of Rogues creatures you control for as
long as you control Sardar, Shadizar Thief.