It leaked enough anyway so I probably won't change much by explaining it. "Wall jump" aka "wj", formerly also "4x jump" or "omg NF SE you only can cheat" is a simple technique based mainly on luck (unless your eyes can register single gameticks), allowing a player to use a flat vertical wall to jump on a height of a regular jump and regain the possibility of double jump. The move is performed by pressing down arrow key exactly at the moment of touching the wall. Jump key must be hold at the same moment. The higher horizontal speed the easier it is to succeed. Plus command "/wc" doesn't affect wall jump in any way (people often ask me about that), neither does the character of choice. With wall jump it's theoretically possible to climb a wall of any given height, in practice people can rarely perform it more than 5 times in a row. It happens though, I once climbed all the way up to the water shield in b1.