Play level 29, "A Tree". You must save ten spirits to complete the level while making sure no spirits are killed by the spikes on either side. Grow a tree to reach the exit. Pause game play when issuing commands to make sure none of the spirits pass the one you are using, or they will get blown into the spikes. Ignore the lone plant in the middle of the level. Start growing upwards and to the right as soon as possible. Keep building the ramp until you get close to the right wall and the wind blows to the left. Then, change the direction you are growing and build upwards and to the left. As your spirits jump off the ramp to the right, the wind will blow them back onto the new ramp. You should pass over the small platform with the plant on it and under the exit spiral. When you are just below the spiral and slightly to the left, the wind should be blowing towards the right. At this point, build a final ramp up and right to allow your spirits to escape.