Actually, I change my reason.
My favorite Pokèmon is Lucario because:
1. While it does have 3 type weaknesses, Phsycic and Flying types deal normal damage (Due to Lucario's Steel type), Normal, Grass, Ice, Ghost, Dragon, and Steel type moves deal half damage, Bug, Dark, and Rock type moves deal only one-fourth the damage, and Poision type moves don't affect Lucario at all and it can't become Poisioned. :]
2: It's awsome. :p
I got 2 favorites:
1.Suicune-after using Calm Mind several times,it's almost unbeatable.
2.Dragonite-a bit slower than most dragons,but it's been my fave since i got my first pokemon game.