Legendary #1:
Xerneas / Yveltal
How to get: During the story towards the ending, you will be stopping team flare, In one of the labs Xerneas for pokemon X will be there and Yveltal for Pokemon Y will be there if you have Pokemon Y then you get Yveltal, if you have Pokemon X you get Xerneas.
Legendary #2 : Zygarde
After beating the game-(Elite four) go to Terminus Cave and go through it. I recommend you watch a video on that here is a link to a video on a quick tutorial on how to catch it here is the video click here
Legend #3 : Mewtwo
After beating the game (Elite 4) Go to pokemon village, When your there go west until you find a river. You’ll need surf for this, Go in the river and go up to this cave not a big cave but, Its a cave. Now go in and you will see Mewtwo standing right by your eyes!
Legend(s) #4 : Zapdos, Articuno, Moltres.
After beating the Elite 4 you need to catch these Legendary birds, For these legendary birds it can be tricky, you need to assume where the bird goes. In this case if you picked Froakie you’ll get Moltres, if you picked Fennekin you’d get Zapdos, if you picked Chespin you’d get Articuno. Now, Keep checking your pokedex to see if these bird(s) are in your area. If not go to a different area, When you run in a patch of grass it will sparkle meaning its the bird. It will run away and you need to keep doing that until its tired of you, It will go to the cave of Sea Spirits Den. use surf to get there and there will be your legendary bird.
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