There are two kinds of pranks in the world: mediocre ones, and the ones that they come up with in Japan. This particular video showcases the Japanese variety. Basically there's a fake foam floor and when you walk on it you fall into a pool of hot water. Water that's hot enough (hot water burn baby!) to warrant hugging a tub of ice afterward. Haha, hurting people is one of the best pranks! (2nd only to making somebody think they're gonna die, then yelling, "HAHA -- GOTCHA!", and then stabbing them. ROFLROFL!)
Thanks to Closet Nerd, who would have run across the water like a basilisk. Herpetology knowledge FTW!