Zekrom is a DragonElectric-typeLegendaryPokémon introduced in Generation V. Along with Reshiram and Kyurem, it is a member of the Tao trio of Unova. Zekrom is also known as the 'Deep Black Pokémon'.
How to Obtain
With a Electric-type Pokémon (That does not need to be pure) and Kyurem in your party, enter the Mausoleum and search in any patches of grass. You must have at least 8 badges in order for this to work. You can also obtain it by redeeming the code "Positivity". (Now expired.)