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Mario starts off on a platform next to Spikes. Donkey Kong throws Poison Mushrooms which shrink Mario if he touches one, leaving him unable to climb Beanstalks and making him weaker in general. Mario must Jump over to the platform on the left then jump up to the vines to grab them then climb them, then he must wait until the moving platform is close enough to him for him to jump on while watching out for Poison Mushrooms. Then once the moving platform is over to right Mario must grab the vines and climb up to the top. Then Mario must go left where he can knock down Fruit which if the Snapjaw is under it will take out the only Snapjaw in this level (and the only treat in this level besides the Poison Mushrooms and Spikes) thus removing any enemies that can harm him, though the Poison Mushrooms will still be there and if he touches one when he's too high up he will get defeated. Mario must simply climb up to vines which has another Fruit on for taking out the Snapjaw just in case he missed the first one, up to the platform with Pauline to end the level with Donkey Kong taking her away again.
Cutscene after level completion
Mario comes in with a hammer, but Donkey Kong and Donkey Kong Jr. are on higher ground and Mario is unable reach them with his hammer. He ends up throwing his hammer upwards, climbs the Ladder, and gets the hammer back again, while Donkey Kong Jr. and Donkey Kong run away, and Mario gives chase with the hammer. The player is then given lives based on their score.