Hey guys, new (casual playing) user here, but I figured you all would know what was going on more than anyone else. I'm currently BS-ing around in the Battle Maison in ORAS, and I switched out my Mega from my Sceptile to my Gardevoir. Now I'll fully admit that the Gardevoir isn't an optimized one at all, but I've been noticing that for some reason when I Mega-Evolve it, it doesn't seem to be nearly as powerful as it seems like it should be. Dazzling Gleam isn't one-shotting most dragons anymore when I try to hit multiple enemies, Moonblast only took out a third of a Slaking's HP, and its stupidly high Sp. Def doesn't seem to be doing anything to protect it even when it's not a super effective hit.
Am I just overestimating the power of my Mega-Gardevoir or is something else going on here?
EDIT: I also just ran into what I can only describe as either a glitch or the game cheating (stupid Maison), I just went up against a Kingdra that had just used its first use of Outrage. Knowing that Dragon attacks do nothing against Fairies I switched to my Gardevoir. All goes according to plan, but the next turn the Kingdra does not go into a third turn of Outrage but instead uses Protect. Now my Sceptile has never been able to de-rage himself regardless of whether or not he's hit something and he certainly has never been able to do so without getting confused, and the Kingdra never ate a berry either so I know that wasn't it. What just happened?