How do you get legendary Pokemon on LeafGreen?

Answer 1

Mewtwo: First have at least 100 Pokemon. Beat the Elite four. Then got o one island and get the first gem. the first gem is in mount ember. but first get lorelei in five island in the ice cave. go back to one islandand and talk to the dude in the big mansion building next to the pokemart. then surf up to kindle road and go sneak up on the two people that is talking. then you get the 1st password to the team rocket base. then talk to both of them and battle them. after you beat both of them, go in the cave and pass it. that's where you find the first gem, don't worry its very easy! When you have the 1st gem, give it to the guy in th mansion in one island. then you have to go to six island and get a Pokemon that knows cut. then go to the dotted hole. use cut. the door opens. inside you find a hole. go to the hole. then you find four holes, go to the north hole, then the one on the left, then the one on the right, then the one down. get the gem. get out. and then go to the guy in 1 island. Good! you got both gems! then go back to vermillion and fly to cerulean city and go to the cave there. go inside and pass the cave and mewtwo is in there!

Articuno: Go to fushia city. have the move strenght and rock smash. surf down in the water. go left until you reach seafoam islands. go in the cave. find all the rocks to push in the holes so you can get to Articuno. once you got all te rocks in the holes, drop down in one of te holes. then surf to Articuno!

Zapdos: Go to Cerulean. go all the way left. go to power plant and enter the building. just keep going until you find zapdos. if you beat him or he faints you cant find him anymore so make sure to save your game when ur there.

Moltres: You can find Moltres in one island! go to kindle road! DONT go in the mount ember. go all the way up and when you see a bunch of rocks, move them around. then moltres is there. SAVE YOUR GAME!!!

Raiku: Beat the elite four and have 100 Pokemon and you can find him anywhere but its hard to catch him because he fleas. I found him at Pallet town.find him if you chose squirtle as your starter.

Entei: Beat the elite four and have at least 100 Pokemon. You can find him at level 50! And you can find him anywhere if you chose balbasaur for you stater.

Suicune: Beat the elite four and have 100 Pokemon. you find him if you choose charmander as your starter.

Mew: I think you cant get him but you can get a cheat code that gets him/ her.

Lugia: Get the aurora ticket by going to a Nintendo event. But you need mystery gift. how to get mystery gift is go to a pokemart. go to the little paper and type in: link together with all. then save your game and turn it off. turn it on and then go to mystery gift. then enjoy your ride to navel rock where you get Lugia and Ho-Oh!

Ho-oh: Get the mystic ticket by going to Nintendo event. then do exactly the same thing as i did with lugia!

Deoxys: Get the mystic ticket and the aurora ticket. go to vermillion city and show the guy your tickets! he gives you a ride to rainbow island. enter and chase around the little triangle until it turns red. then deoxys appears.

I hope these helped! I don't know when the next Nintendo vent is but it works i swear! The rest of the legendaries you have to trade with your friends! Thanks for viewing! :) :) :) :) :) :) :)

Answer 2

Normally there are speacial events but not in this game, If you want Articuno there is a cave you go to the bottom of, Zapdos is in the power plant, and moltres is located in Victory Road (I think). Mewtwo is a differtent story, first complete the Pokemon league go to the cave near cerulean city, go down all the way and find Mewtwo (there is much more legendaries though =D)
There are fewer legendary pokemon in leaf green than in, say, diamond or pearl, but:

Zapdos - Electric/Flying - You find it in the Power Plant south of the Cerulean entrance to Rock tunnel (Requirements - Surf)

Moltres - Fire/Flying - You find Moltres at the top of Mt. Ember on One Island (You get to go to One Island after beating Blaine (Requirements - Strength)

Articuno - Ice/Flying - in the Seafoam Islands, it's advisable to surf from Fuschia City because there are a few puzzles (Requirements - Surf, Strength)

Mewtwo - Psychic - You find Mewtwo in Cerulean cave after beating the elite 4 and getting the ruby and sapphire for the machine on one island (Can be a bit of a bitch) (Requirements -Tough Pokemon, Rock Smash, Surf, maybe Strength, I forget atm)

and one of the legendary beasts (Entei, Raikou, Suicune), and it is roaming Kanto after you beat the Elite 4, and is the type that is strong against your starter (if you chose charmander, Suicune will roam Kanto, Bulbasaur-Entei, Squirtle-Raikou)

I think these are the only ones you can obtain legitimately and without trade