You forgot some things. When you put something in a chest, it will lagg so hard. So you need to add a InventoryClickEvent to solve that
I like the plugin where you can pilot a air balloon, but those plugins aren't good for big servers. But if it is with your friends I would...
Hmm, nice idea to let players become invisible when they shiftclick. Nice tutorial for those new bukkit coders!
You can create a method for this kind of things. Every time you want to store a location, player inventory,... then you can call that method. And...
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