Big pitching arms
Power pitching is considered the biggest postseason weapon, and the Pirates have the best power tandem in their history in Gerrit Cole and Francisco Liriano, two 200-strikeout pitchers in one rotation. They've had only five of those all-time, and a third is A.J. Burnett, who may no longer be regarded a pure power pitcher but can still rack up K's with his curveball.
And the big arms pitched up to the competition, just as the Bucs seemed to play up to it. That trio's collective record against .