Those Annoying Mimics
In the Omega dungeon, you may ( probably ) will come acroos a chest in battle. My advice: Don't steal from it! Use Mug instead... Assuming you have it of course. Which you should by this time. If you do steal from it, it might be just a mega potion or something or it might be a Mimic, Which has very high HP, gives you all but no AP, and no items whatsoever. Avoid it completely using Mug if you can.
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