To get Captain Olimar trapped, go to the Forest Of Hope stage on Day 2. Take out your Red Pikmin and have them break down the nearby gate. Next, have Olimar run to the left and through the water pond. Run off the cliff into the area with the Nova Blaster. You have now gotten Captain Olimar trapped since there is no way out. You can leave the Nova Blaster area through the hole in the stump but you cannot get back to the Shock Absorber area, the Landing Site, the Yellow Onion, the Burrowing Snagrets area, or the area through the first gate. To escape, bring Yellow Pikmin with you and arm them with Bomb-Rocks in the can near the Nova Blaster.