1st Secret Room
go to the 1st Ruins of Alph puzzle room. read the message in the back. it says "escape". use an escape rope. u'll be outside. go back into the room to find a secret passageway.
2nd Secret Room
go to the 2nd puzzle room. read the message written in the back. it says "light". use flash by there to open up the 2nd secret passage.
3rd Secret Room
go to the 3rd puzzle room. read the message on the back wall. i think it says "water". anywayz, get a water stone and carry it with u to the puzzle room. the secret passage will open.
4th Secret Room
to to the 4th puzzle room read the message. it says "Ho-oh". catch Ho-oh and bring him to the room. the 4th and final secret passage will open.
use Suicune to battle in the level 40 Battle Tower competition. a person will tell u to bring a Lugia to show him. bring a Lugia and he'll tell u a secret. visit Prof. Elm and he'll challenge u to a battle. if u beat him, he'll tell u about Pokémagic and the 6 Pokémon orbs. he'll give u an ancient rock. go to the Whirl Islands (any one) and toss the ancient rock. six new caves will rise out of the water. each cave contains 1 Pokémon orb. use the Pokémon orbs for magical powers during battles.
breed a female Alakazam with a male Meganium. the result is that both parents will disappear and Celebi is in the egg they produce.
talk to Copycat in Saffron City. talk to her as fast as u possibly can. she'll finally tell u the secret to mimicking people. now u can mimic people. press 'select' when talking to someone to mimic them. they'll get mad and walk off.
beat Red and go to the Goldenrod Dept. Store. read the message written on the right side of a phone. a black-haired nurse will ask u to get all 16 badges. when u do, go back and talk to her to get the GS Ball. brign the GS Ball to Kurt and let him examine it. wait 1 day and take the ball back. put it in the Ilex Forest shrine. Celebi will come to battle u.
lose all of ur money except for 1 dollar. sell all ur items. talk to Red's mom Prof. Oak, Prof. Elm, and Mr. Pokémon (in that order) for one week. on the last day that u do this, Prof. Elm will call u to tell u that Prof. Oak is dead. he'll also give u instructions on where to go for Oak's funeral. u'll discover a new place. while the others mourn, u can explore the grassy area surrounding the funeral. u'll encounter very rare Pokémon there.
beat Misty and fly to Silver Cave. find Red to discover a key. go to the underground path in Goldenrod City. unlock the suspicous looking door to find that it will be different than before. go in there to find Pimew.