The Zet Tree was actually recorded twice by German LIMBO runner Zet. It requires a precise jumping after pushing the log from the tree into the lake. By jumping from the log you stand on and first pressing left, then right, as soon as you have the feeling you are jumping too far for the standard strat, the boy will make a climbing movement that somehow can be aborted by a jump to the right. This jump then will completely skip the log beyond the boy and he will instead grab the small log to the right. An optimized Zet Tree might save no more than 0.5 to 1 seconds.