I wonder why this old post was brought back up.. Mega Kangastan is so easily defeated.. I have absolutely zero problems with it.. Xatu can totally disable it's ability to double hit by taking away it's Parental Ability, Mewtwo can outspeed it and Aura Sphere 1 hit-ko it, Talonflame can out priority/speed it with acrobatics to drop it's health considerably, Xerneas can one-shot it if geomancy'd, otherwise hurt it heavily if not, Zekrom can survive a dual return then proceed to one-shot it with an ultra powerful fusion bolt, Virizion can outspeed and one-shot it with sacred sword, etc.. there's just so many pokemon who can take out Kangastan.. but the best is Xatu in my opinion, my opponents never think that it's a threat, so it usually goes ignored while they focus their efforts on hitting my other Pokemon but then SURPRISE!!! it makes Kangastan useless by taking away it's ability completely, that afterwards, I ignore it and let it live for a round or two while I refocus my efforts on taking out the other Pokemon in double/triple battles as i know a single return, power-up punch, etc, won't do much damage or kill any of my Pokemon...