it isn't based on luck you nub
http://www.gamefaqs.com/console/ps2/file/932312/50034"On every turn Fortune will use Wheel of Fortune, which summons a giant
spinner. There are three different spinners: one will inflict the Panic,
Distressed, Enraged, or Afraid ailments; One which casts Matarukaja,
Matarunda, Marakukaja, or Marakunda; and one which will either heal for 50 HP
or damage for 50, 100, or 200 HP. Which side these spinners effects depend on
the color it lands on, if it land on a blue section the result will be
favorable to you, While if it lands on red the result will be bad.
Being able to control which side comes off worse on the Wheel of Fortune is
the key to this battle. What you want to do is be looking not at the pointer,
but rather at a spot directly opposite of the pointer, as that is where the
spinner will end up when it’s stopped. What I do is from your point of view
use where Fortune intersects the far edge of the spinner as a reference
point, then move this spot over a few tics to the left. This is the spot
where the pointer is going to land when you press the X button."