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How to Get the Lazy Shell Weapon and Armor
Super Mario RPG contains many different weapons and equipment that you can collect for your party over the course of the game, and while most are gotten from merchants in shops, there are a few extremely good weapons found in chests that can easily be missed!
The Lazy Shell is considered Mario's best weapon by far, and comes in both a weapon and armor variant (that drastically reduces defense but also your attack), and is hidden away in a secret location that requires you completing a side quest to find. To do so, you'll need to claim a Seed, Fertilizer, and find the Rose Town Gardener.
Where to Get the Seed
The Seed is one half of the special items you need to get the Lazy Shell, and luckily its part of the main story and is hard to miss.
You'll find it when going through Bean Valley on your way to Nimbus Land. Defeat the boss known as Megasmilax, and you'll receive the Seed after the boss has been beaten, by interacting with a small note just north of the warp pipe.
Where to Get the Fertilizer
The Fertilizer is the second half of the special items you need to get the Lazy Shell, and its very well hidden.
It's located in Nimbus Land, but cannot be claimed until after you have cleared the Nimbus Castle, and defeated Valentina, restoring the castle to its former glory and ridding it of bad guys.
Once you've done that, head to the far right of the Nimbus Land town to find a home where Croco is stealing from (if you go inside, he will dash out the front door).
From the front door of the house, move directly south along the edge of the cloud borders, then try walking down to to the right between two cloud tufts on the lower part of this ledge. If done correctly, you'll walk out onto an invisible path leading to the Shy Guy gardener that watered Birdo.
Now that you've caught him, he'll offer you the Fertilizer in exchange for letting him go!
Where to Find the Gardener and Lazy Shell
Now that you have both pieces needed, return to Rose Town, and head up to the northeast section of the town in the middle to find a new path has been created leading out of town.
This will lead to a lone house on the town outskirts, and inside you'll find a Gardener you can talk to who desperately seeks the perfect seed and fertilizer.
Hand them over, survive his long-winded ramblings, and wait for a giant beanstalk to erupt out of the house!
Head outside, and jump up the crates up towards the chimney, and you'll be able to climb the beanstalk up into the clouds.
When you reach the top, you'll arrive at a cloud platform that holds both the Lazy Shell Weapon, and Lazy Shell Armor!