Best Speed Effort Values Training Spot
If you're looking to boost your Pokemon's Overall Speed Stat through Effort Value (EV) training, look no further than Diglett Cave. If you simply walk throughout the cave, there is a 95% of a Diglett appearing. And every Diglett you defeat will give you 95 EVs towards your Speed Stat. Dugtrio will appear the other 5% of the time, giving you 120 EVs for each defeat. Since these Pokemon have a constant appearance rate, a player can literally walk into battling over and over and abuse this in order to get their Pokemon a better Overall Speed Stat.
Players can also use the item Carbos to boost their Pokemon's Speed EVs, increasing the EV Stat by 2,560 until the first 25,600 Effort Values are reached for the stat.