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The level has Mario start on the ground to the left. Mario must climb up the ladder then go right, jumping across the blocks when the Purupuru are not in his way and making sure he's not on the blocks long as they can push him into the spikes, though he can stand on them and jump off of them to get up higher. Mario then has to land on the platform with the ladder and climb up it. On the platform above, Mario must watch out for the Penpens as they can defeat him. Mario can use one of the Penpens to defeat the other by throwing it. He should then pull the switch to open the door (and activate the bridge), then he must grab the key and head out. Should he fail and the key goes back to its spawn point, he can use the block which is above the first platform, or the spring block which is to the right of the first ladder on a slightly raised big block, and place it near the platform the key is on to be able to get back up to the platform quicker. With the key, Mario must once again jump across the blocks while watching out for the Purupuru until he reaches the other side. Mario then has a choice of either throwing the key onto the bridge, then climbing up the ladder, flipping the switch to deactivate the bridge, quickly going down the ladder, and going down to where the key is; or he can keep the key and try to land on the block with the Purupuru and drop to where the door is without falling onto the spikes. If he does either choice successfully, he can simply head to the door with the key to complete the level.
Pauline's lost items
Within this stage, Pauline's lost items can be found in the following order and in the following places: