i found a rainbowrayquaza that was created on may 13 of 2013 ands rainbow rayquaza was created long before. i dint know if its a hack or a event but i need to know

That's because RainbowRayquaza is created from the Battle Towers, you'd need a RainbowKey (Lucky dip) and once you beat it, you get a RainbowRayquaza as prize. Another can be created whenever really.

oh dang i didnt know that! i need a rainbow key than. thanks tho

Exactly what phoenix said. It's just different times because r.keys are hard to get and people beat the RainbowTower on different times/days. Not a glitch.

is the tower really hard? if i get one i dont want to waste it just like that.

We get rainbowrayquazas from the rainbow battle towers which is unlocked by rainbow keys :) the tower is really hard so u need to assimilated right types of pokes and at same level and hope u can win on the first try.