Skaven Nightrunner

Strategy Point Cost (20)
These vile creatures that excel at speed, stealth,
and duplicity advance amongst their own kind,
well on the road to one of the bloodiest and
most feared of Skaven." S. Adelburg, Scholar
Deliver a successful sneak attack, causing 3d6+6
piercing damage to a single opponent, OR
block another strategy card's use (card is spent)