I really want to complete my National Dex but I missed a lot of the events so I was just wondering.
>In Pokémon Black and White, Professor Cedric Juniper upgrades the player's Pokédex to the National mode when the player first leaves his/her own house after defeating N and Ghetsis. As with previous generations, event Pokémon including Keldeo, Meloetta and Genesect are not needed to complete the National Pokédex.
If you mean the full 649, yes, you need events. Definitely. I believe it's impossible to complete a national dex without hacks, as there are some Pokemon that haven't been released for events. Such as Shaymin. Genesect. Meloetta. So, sorry...