From Tenipuri Info
Tsubame Gaeshi is a forehand shot with a slice spin. It is one of the Triple Counters.
A counter against topspin shots. The user utilizes the opponent's topspin to hit a slice return with twice the original spin. Upon hitting the ground, the ball does not bounce, but instead slides forwards without bouncing.
Houou Gaeshi: The evolved version of Tsubame Gaeshi. It causes the ball to hit the ground even sooner.