Splatoon offers a lot of content for Nintendo fans, both young and old. The ink based team shooter is friendly for all ages due to a lack of voice communication.
Splatoon took the Wii U by storm as a completely new IP from Nintendo. Although we have games like Captain Toad Treasure Tracker, the character and setting isn’t exactly new.
Splatfests are a special event within Splatoon, where players choose a different team to splat for. The contest will run at the same time globally, however players are region locked. Results will be tallied by region. (source)
This upcoming Splatfest, which will run from February 19th at 10:00pm PT to February 20th at 10:00pm PT will feature Pokémon Red and Pokémon Blue. This is one of the first, if not the first, Splatfest to run world wide simultaneously.