'Pokémon Sun and Moon' players will soon be able to get their hands on an exclusive Ash Ketchum Pikachu.

The six exclusive Ash Ketchum Pikachu styles

The six exclusive Ash Ketchum Pikachu styles

The latest instalment of the hugely popular RPG - which was released for the Nintendo 3DS in 2016 - has a surprise in store for players, as, starting this month, they'll be able to get their hands on one of six different kinds of the franchise's mascot monster, as seen in the animated television series as protagonist Ash Ketchum's best friend.

Each of the six variations of Pikachu comes wearing a different style of Ash's hat - which changes from series to series in the anime - and has a set of moves similar to the moves used by the character at the corresponding time in the show.

Beginning September 19, Nintendo will release a special code via their website pokemon.com, which will allow players to receive one of the Pikachu variants. However, players will only be able to load one of the styles into their game, so they must choose the one they want carefully.

September 19 to 25 will give players the chance to get Pikachu wearing Ash's hat from the original series (based on the Red, Blue, and Yellow games), September 26 to October 2nd will see Pikachu in the Hoenn hat (from the Ruby and Sapphire games), October 3 to 9 features the Sinnoh Hat (Diamond and Pearl), October 10 to 16 is for the Unover hat (Black and White), October 17 to 23 for the Kalos hat (X and Y), and players can grab the Alola hat from the current Sun and Moon series from October 24 to 30.

The exclusive Pokémon deal comes as a promotion for the upcoming movie 'Pokémon the Movie: I Choose You', which revisits the iconic story of how Ash Ketchum came to be friends with his Pikachu.

The movie is being released in honour of the 20th anniversary of the first episode of the anime in which Ash receives the unruly Pokémon from Professor Oak.

'Pokémon the Movie: I Choose You' will have a very limited international theatrical run from November 5 to 6.