Black Widow

Menace, Haste, and Flanking
(Whenever this creature becomes blocked by a creature without flanking, the blocking creature gets -1/-1
until end of turn.)
When Hawkeye is on the battlefield, put a +1/+1 counter on Black Widow.
When Hawkeye leaves the battlefield, remove a
+/1+/1 counter from Black Widow.
Madame Natasha but you... can call me
The Black Widow!