"It stands rooted and still in one spot all day long. People believe that this Pokémon does so out of fear of the terrible things it has foreseen in the future."
Xatu is an incredibly powerful Pokemon, not the least of which is because of its variety of moves and abilities due to its dual typing. In even lore, Xatu's psychic power is incredible. As you read in the Pokedex entry, this Pokemon can see into the future, and it's been shown to do that in the anime as well.
Xatu's Basic Attacks are Air Slash and Feint Attack, while its Special Attacks are Future Sight, Aerial Ace and Ominous Wind.