By request of some people asking on how to get godly stat on arena, it's actually pretty easy.
Note: this is bug, I don't really recommend you using this, but whatever, bug is also a feature :D , if you want to use this go ahead.
Touch me and you'll dead in second.
For this trick, all you need is a party (3 ppl or so including the bard, so the party won't break) with a bard who have music skill to buff stat (In this case, I'm using pop)
1. Make a party at arena with the bard inside
2. Have the bard cast pop
3. Immediately remove the bard from party
4. Wait until the music is over, then invite the bard to rejoin the party
5. Repeat from step 2.
And that's it, the bonus should stack infinitely. Be warned that:
1. You mustn't get any other buff, including HF, if your bard want to use HF, confirm that she's outside the party
2. If you're dead, and getting resurrected, the stat will go back to normal. This also applies to getting back to the savepoint. But there's an exception that if you save at downtown and you get back to that position, the stat will not reset.
Well that's it, basically with this you can massacre a lot of ppl in arena, if you get enough time to prepare.