Why is it that even a Mountain Storm hitting a level 1 Aron with a critical hit AND being super effective wont kill it?

Question

I saw a video of it, here it is http://www.youtube.com/watch?v=oJxvmtCwAZY&feature=related

Answer 1

It has the ability Sturdy, which acts like a Focus Sash. It cannot KO you in one hit, you will survive with 1 HP.

Comments

i would up vote it but its a to easy answer :)