@Storegrove:
Mizu Mizu no Mi: The ability to become and control water
That would be awful for the user, seeing as they can't swim. XD
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Salt Salt fruit xD I've always pictured a pic of an OC rubbing his fingers together over a dish of sanjis (seasoning it with his salt) and sanji raging in the background and the OC saying "hey, you chose to screw up your sense of salt when you started smoking". hahaha, it's funny cuz im a cook.
This sounds hilarious. :) I'm not sure if it's exactly combat-ready though.
Here's a devil fruit of my own inventions: http://www.arlongpark.net/showthread.php?t=3683&page=107&p=3401085&viewfull=1#post3401085
I think it would be difficult to fight against, if the user knew what they were doing.
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What about Guru-guru no mi? You can just...make things spin. Rapidlye and without control.
That sounds familiar. Does it already exist?