How to get Mewtwo in mystery dungeon?

Question

Been searching all day, and had no luck; Help please.

Answer 1

Mewtwo is found in the Western cave. To get there, you need to complete the Spinda quests that involves Raikou, Entei, Suicune and Ho-oh. Complete that quests and tell Spinda your tale. Then go back to Mt. Faraway and recruit Ho-oh.

Once you recruit Ho-oh, there will be a short cut-sequence with Charizard and Blastoise exploring a new area only to be devastated. They will tell you about the new area, the Western cave.

Western cave is one of the toughest dungeons in the game. It starts out gentle, with pokémon like snubble and venonat. But the dungeon is 99 floors deep, and you will eventually be fighting stage 2 evolved pokémon such as Charizard, Alakazam, Swampert and even Tyranitar.

Mewtwo is on the 99th floor. It is very tough and likes the use of confusion. You can't recruit Mewtwo the first time you fight it, but subsequent times you fight it, it may ask to join you. You need a specific friend area to recruit it though. I can't remember the name of it. i think it's something like eerie cavern, but don't hold me to it.