From the Super Mario Wiki
The Luiginary Typhoon is the sixth and last available Luiginary Attack in Mario & Luigi: Dream Team. The Attack Pieces for this attack are found in Dreamy Somnom Woods, and it costs 16 BP to use, making it the most expensive Luiginary Attack in the game. Dreamy Luigi holds his right foot up and raises both hands into the air as if he were spinning like a typhoon before this attack begins.
When used, Mario moves away from the enemies, and Dreamy Luigi spawns a tornado structure composed of Luiginoids with Mario holding a Luiginoid rope composed of smaller ones. When the player presses the button, Mario will tug on the Luiginoid rope and the Luiginoid tornado will be pulled towards him, the player having to press the button as the Luiginoid tornado approaches to whip it into a great typhoon full of Luiginoids. The less time left when Mario unleashes the Luiginoid tornado, the greater the size of the typhoon. If the player fails to press the button while Mario pulls in the Luiginoid tornado at the start of the attack, he will be flung into the enemies and the attack will end with little damage done.
The player can move the typhoon towards the enemies with the to snatch them into the air damage them. If the player rapidly presses the button, the Luiginoids will take out their hammers and spin with them, which will deal even more damage to enemies caught in the typhoon. The more carnage caused by the typhoon, the greater the rating the player receives, ranging from "OK!" to "Excellent!" ratings.
Wind up the Luiginoid rope, and yank it with the A Button for a typhoon. You can move the typhoon with the Circle Pad to swallow up your foes. Rapidly press the B Button to deal more damage with the Luiginoids' spin!
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