Simplify the following text for a Grade 5 native English-speaking person.
Original: They called it a good contender to Mewtwo , as well as an unpredictable PokÃ mon due to its ability to use any TM or HMs , items that teach PokÃ mon attacks .
Simplified: Mewtwo appeared in two movies : PokÃ mon : The First Movie and PokÃ mon : Mewtwo Returns .