Athenodoros
Official Smogon Know-It-All
@ pokeMONstar: in order to have even defenses, Celebi can have a 252 HP/180 Def/76 Sp. Def in order to have even defenses, because Sassy is a +Sp. Def. nature.
However, Celebi generally invest more in their Defense stat because of the large number of physical attackers in the metagame, so you could well have all Defense EVs.
@DarkJester: It is a quirk of Gen. IV because Diamond and Pearl did not have the Rotom Formes, so they cannot be used over Wifi. There are Hacks that can be used, but for most people that is not practical. If you are in Ubers, you could use Giratina, but in OU you could only really use Gengar or dusknoir, barring UUs like spiritomb.
EDIT: Dammit Haunter.
However, Celebi generally invest more in their Defense stat because of the large number of physical attackers in the metagame, so you could well have all Defense EVs.
@DarkJester: It is a quirk of Gen. IV because Diamond and Pearl did not have the Rotom Formes, so they cannot be used over Wifi. There are Hacks that can be used, but for most people that is not practical. If you are in Ubers, you could use Giratina, but in OU you could only really use Gengar or dusknoir, barring UUs like spiritomb.
EDIT: Dammit Haunter.