A new Pokémon has been added to 'Pokémon: Sun' and 'Pokémon: Moon'.

New Pokémon added to Pokémon Sun and Moon

New Pokémon added to Pokémon Sun and Moon

The new mythical creature, named Marshadow, has been rumoured to be appearing in the latest instalments of the popular role-playing games - which are developed by Nintendo - since November, but a video posted on the Official Pokémon YouTube Channel has revealed the new pocket monster will be available to players very soon.

The 16-second video features a short clip of Marshadow in battle before telling players that "more details are coming soon".

According to a message written on the game's website: "Marshadow cannot be encountered in normal gameplay. Details will be introduced in the future on how Trainers can get this Pokémon for their game."

Marshadow is believed to be a fighting and ghost type Pokémon with no known evolutions, according to Pokémon encyclopedia website Bulbapedia.

As of yet, it is unclear when the new Pokémon will be available or how players can get their hands on it.

The game's last mythical Pokémon, Magearna, was released in December and required players to scan an exclusive QR code - which is still active at the time of writing - after finishing the main story of either 'Sun' or 'Moon'.

Meanwhile, in November it was revealed the newest instalments of the popular franchise had shattered record sales for Nintendo.

In Sun and Moon's first day of sales alone they smashed Wii Fit's first two weeks of record sales from 2008.

The game's launch numbers were double those of fellow 3DS games 'Pokémon Omega Ruby and Alpha Sapphire' back in 2014, according to UK numbers company Chart-Track - although these were remakes of earlier games.