Moltres is one of the few Legendary Pokemon that can be found within Pokemon FireRed, being one piece of the Kanto Legendary Bird Trio. Moltres will most likely be the second or third Legendary Pokemon you encounter within the game, since it's found on One Island (apart of the Sevii Islands) that can't be accessed until after obtaining the Cinnabar Island Gym Badge. Moltres can be found at the the far northern tip of One Island, on a mountain that is called Mt. Ember. Before reaching Moltres on Mt. Ember, you must first solve a Boulder Puzzle that will require HM Strength. Moltres awaits just after this puzzle.
Moltres will be found at Level 50, and it will know the moves Fire Spin, Agility, Endure, and Flamethrower. Since Fire Spin and Flamethrower are Moltres' only attacking moves, they're really the only thing you will need to worry about. Since Fire Type Moves aren't effective against Rock Type Pokemon, they are usually the way to go when facing this Legendary Bird. Moltre is also a Fire/Flying Type Pokemon, meaning its especially weak to Rock Type Attacks. Electric Type Attacks also hit Moltres extremely hard.
When looking to catch Moltres, always save directly before proceeding to battling the Legendary Bird. It's never fun when you accidentally defeat Moltres or if it defeats all of your Pokemon, but all of that is avoidable simply by saving directly before trying to catch it. Also, don't forget to purchase loads of Ultra Balls and Repels from the Poke Mart before going to catch Moltres. Repels will help you avoid facing Wild Pokemon leading up to Moltres on Mt. Ember, and Ultra Balls are the best possible Poke Balls you can use when trying to catch Moltres (since it's not worth using your one and only Master Ball on).
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