The Twisker Sock or Twisker Punch is Popeye's most devastating fighting technique, and he has been seen to use it in comics, film and animation. It is not a very common sight, though: as he explained to Bluto during their first encounter in the Thimble Theatre comic strip, Popeye's ultimate attack is potentially lethal, so the sailor would only use it against his mightiest foes.
The attack consists of Popeye twisting his forearm muscle until it is completely wrapped unto itself, then striking at his opponent. This not only grants the punch increased force but may also cause the victim to spin vertically as Popeye's forearm becomes unwrapped.
Gallery
A Twisker Sock readied in Popeye the Sailor Meets Sindbad the Sailor