Zubat Ev. Rock and steel type pokemon such as kabuto will be troublesome. Zubat also renders ferroseed useless.
Ev is short for effort value. 50 flying national pokédex hoenn pokédex abilities hidden ability 041 065. Ev zones are areas in every region that have specifically built spawns to enhance the proficiency of ev training that would other wise be unavailable in any other areas in the game.
Other options zubat can pull off a nasty.
Pokémon omega ruby alpha sapphire may actually offer the best ev training experiences in any pokémon game due to how fast and consistent it is. Cerulean city cinnabar island lavender town pallet town seafoam island basements 3 4 krabby. 1046 行 ev pages about evs hp 132 attack 297 defense 179 special attack 207 special. Rock and steel type pokemon such as kabuto will be troublesome.