The Bite-Sized series of articles is meant to take the most powerful cards in Dominion and give a short explanation of what makes them powerful.
Torturer is one of the only discard attacks that stacks with multiple plays, meaning that you can force your opponent to either take a lot of Curses or discard all the way down to zero cards in hand if you can play enough Torturers in a turn. For this reason, Torturer is the focal point of most kingdoms where it appears with a village.
Keep in mind that you shouldn’t always discard to Torturer — if you give up chances to play your own Torturer, your deck may stay clear of Curses but you won’t win. Most games like this revolve around just playing as many Torturers as possible until one player has been beaten into submission. Only strong trashing can prevent this kind of scenario, because that type of deck can power through the Curses until they are gone, rendering Torturer’s attack mostly inert.