Landorus is a Legendary Pokémon that is exclusive to Pokémon Black. This is a deliberate design choice by the developers to create a sense of exclusivity and encourage trading between players of the two versions.
However, you can still obtain Landorus in Pokémon White by:
* Trading with someone who has Pokémon Black: This is the most common way to get Landorus.
* Using the Poké Transporter and transferring it from a previous generation game: This method is only possible if you have access to the Poké Transporter and a previous generation game that has Landorus.
Remember, Landorus is a powerful Pokémon, so it's worth the effort to acquire it for your team. Good luck!