Can I use a Max Potion on a Pokemon with no damage counters on it or energy attached to it? Can I use a Max Potion on a Pokemon with no damage counters, but it has energy attached to it?
Q. Can you use Max Potion to heal a Pokemon that doesn't have any energy attached to it?
A. Yes, you can. (BW:Emerging Powers FAQ; Sep 1, 2011 PUI Rules Team)
Q. Can you use Max Potion on a Pokemon with Energies attached but no damage on it?
A. No, you cannot. If you don't have any damage, you cannot use Max Potion on that Pokemon. (Feb 16, 2012 TPCi Rules Team)