Kenji-kun;2448026xplain. [Back on topic said:Celebi can transcend time, and Jirachi grants wishes, Manaphy does... something; but Mew has "the genetic composition of all pokemon", which includes Celebi, Jirachi, Manaphy, and every other legend & normal pokemon. Mew is strongest.
Mew -_-;
Has the Genetic Composition of all of them. Has the movepool power to destory all of them, and its stats aren't to shabby...
Shaymin has a poor movepool, so it gets killed by Mew's Greater Movepool
So there
It's second only to Arcues