To keep celebrating 20 years of Pokemon, 3DS trainers should always be ready to set out for an adventure this whole week because Nintendo is distributing Pikachu for Pokemon Sun and Moon.

The free and special Pikachu this week will be seen wearing the hat Ash wore during his battles in the Sinnoh region. This version of Pikachu will be able to use the 10,000,000 volt Thunderbolt Z-Move by utilizing the Pikashunium Z crystal inside the hat. Regular attacks of this event exclusive Pikachu include Thunderbolt, Quick Attack, Iron Tail, and Volt Tackle.

To acquire the free Pikachu, players are asked to select Mystery Gift from the main menu of Sun or Moon and then select Receive Gift. Input "PIKACHU20" for the code being asked. The free Pikachu will be ready for the player to pick up in any Pokemon Center found in the game. However, players who redeemed the two Pikachus from before will not be able to use this code.

The Sinnoh Pikachu is the third special version of Pikachu that Nintendo has released. The first one was from Sept. 19 to 25 where Pikachu is wearing the original hat. The Hoen Hat Pikachu was just last week, Sept. 26 to Oct. 2. Next up for release after this week is the Unnova hat from "Pokemon Black/White," which will run from Oct. 10 to 16. This is followed by the Kalos hat from "Pokemon X/Y" for the Oct. 17 to 23 schedule. Finally, the Alola hat from "Pokemon Sun/Moon" will be released from Oct. 24 to 30.

As announced by Nintendo, each exclusive hat-wearing Pikachu will have a different skill set corresponding to the attacks and moves Pikachu and Ash did in the respective series.

In line with the Halloween season, the Mythical Pokemon Marshadow will also be distributed to the game starting Oct 9. GameStop is giving away the free code for the ghost Pokemon for U.S. players who visit their store.