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The Magical Seed is a seed which can grow flowers wherever they are planted. In Paper Mario, Mario must find four of these, which are usually held by Bub-ulbs, so that he can gain access to Flower Fields. The doorway is the archway by Minh T., in front of the post office in Toad Town. Each time Mario gets a Magical seed from a Bub-ulb, one of the seeds will have a different color.
These are the seeds locations:
Names in other languages