@ Diakuren:
I would probably say that a Swords Dance Rayquaza would be the way to go, since Dragon Dance relies far more on its speed than a SD set does (SD uses Extremespeed as its main way of damaging stuff that would outspeed it)
Rayquaza @ Life Orb
EVs: 252 Attack/ 252 speed / 4 Defense
- Swords Dance
- Extremespeed
- Dragon Claw
- Earthquake/Overheat
SD + ES kills stuff that's faster than you, Dragon Claw is there for a semi-mandatory stab (Outrage would make Rayquaza much easier to revenge kill due to the fact that it would lock it in the move, preventing you from using Extremespeed), and Earthquake damages Steels in general, while Overheat might be used over it to kill Scizor, Forretress, and Skarmory.
@Anis:
After you've reached 510 EVs (In your case by smacking around Zubats, Chanseys and Testacools), you have reached your limit and will not gain any EVs from fighting other pokemon, unless you remove some of them by feeding them EV-reducing berries.
You do not have to fight 252 Zubats in a row to get 252 EVs in Speed, they add up over time.
IVs = Individual values that range from 31 to 0, and determine a pokemons stats when hatched/caught. Generally speaking, a pokemon with a 0 IV in speed will (at lvl 100) have 31 points less in speed than a pokemon with a 31 IV in speed, hence, it is important to make sure that your pokemon have at least decent IVs before you start to EV train them, in order to reach their fullest potential. You can determine the IVs of a pokemon by using an Action Replay device, using various IV calculators on the web, or simply by having an IV battle (at least in Gen 4 games). If you are trying to determine the IVs of a pokemon, make sure to record how many EV it has gained, as if you lose track it will be hard/impossible to make sure what the IVs really are.
ALSO, your name creeps me out.