A fastener driver includes a cylinder, a moveable piston positioned within the cylinder, and a driver blade attached to the piston and movable therewith between a top-dead-center (TDC) position and a bottom-dead-center (BDC) position. The driver blade including a body and a plurality of teeth extending therefrom. A lifter is operable to move the driver blade from the BDC position toward the TDC position. The lifter including a plurality of lugs engageable with the teeth of the driver blade when moving the driver blade from the BDC position toward the TDC position. The body of the driver blade has a first thickness and at least a first of the teeth has a second thickness that is greater than the first thickness and the first tooth has a stepped configuration relative to the body.