photon booster.

[Jimbo1990]

well to answer you question correctly you can only use a photon sphere once BUT you can use aphoton booster up to 3 times on each stat (though you'd need 3 photon spheres) but only if the stat doesnt go over 100% so you can use it on 70% to make it 100% but if its 75% then you can't use it, i hope that makes sense
and they cost alot so i wouldn't use them all willy-nilly