The panda-punching class in question is the male Brawler, who is arriving in the March 13th Counterpunch update (the action MMO previously added the female Brawler in a past patch). Mechanically, the male Brawler is identical to his female counterpart, although he will sport different skill animations.
TERA’s Counterpunch is also bringing back a slightly reworked Ruinous Manor dungeon, throwing in a leaderboard system for monthly seasons, and triggering a series of free giveaways. There is an additional character slot (March 13th through the 20th), a free special lootbox (March 17th and 18th), and a level up box for male Brawlers (March 13th through April 10th).