I am going to apologize now because what I am going to say can be considered rude and I will probably be warned for being a mini-mod, but I have to say this. I just hope those that have posted here can accept some constructive criticism.
When someone asks a questions, they are hopefully expecting good information in return. If you are unsure or not experienced enough to provide the answer, PLEASE do not post. While you think you might be helping, all you are really doing is increasing your post count, and providing inaccurate information that only wastes the time of not only the person who asked the question, but many other members here that would read it and think that it was correct information. Before you provide an answer, at least research it and make sure what you are offering is correct.
I won't single anyone out in particular, but here are a few facts:
* The best Pokemon to use against Wattson is a Ground-type (Mudkip, Geodude, etc.) that is immune to Electric attacks.
* EV points accumulate with every battle a Pokemon participates in. Every 4 EV points earned in one stat will increase that stat by 1 point the next time it levels up. There is no minimum level.
* X Special has no effect whatsoever on a physical move like Mud Slap. Those X items are a complete waste of money anyway, but that is a topic for another time.
* Unless it was changed in DPP, Magneton does not have the Levitate Ability. It has either Magnet Pull or Sturdy. I always suggest Magnet Pull, as it allows you to switch into Steel-types and prevent them from switching out, allowing you to KO them easily.