 Today some of the sharpest opening variations have been analyzed so deeply that they are often used as drawing weapons . For example , at the highest levels , Black often uses the Marshall Attack in the Ruy Lopez , a line where Black sacrifices a pawn for strong attacking chances , to obtain an endgame where Black is still a pawn down but is able to draw with correct play . 
 Today some of the sharpest opening variations <a href='been_done' title='1'><mark>have</mark></a> been analyzed so deeply that they are often used as drawing weapons . For example , at the highest levels , Black often <a href='uninflect' title='2'><mark>uses</mark></a> the Marshall Attack in the Ruy Lopez , a line where Black sacrifices a pawn for strong attacking chances , to obtain an endgame where Black <a href='drop_aux' title='3'><mark>is</mark></a>still a pawn down but <a href='drop_aux' title='4'><mark>is</mark></a>able to draw with correct play . 
Today some of da sharpest opening variations done been analyzed soo deeply that they are often used as drawing weapons . fa example , at the highest levels , Black often use tdaMarshall Attack in the Ruy Lopez , a line where Black sacrifices a pawn for strong attacking chances , to obtain an endgame where Black still a pawn down but able to draw w/ correct play .