Miiverse

Miiverse is a social network incorporated into Splatoon, allowing conversation about video games on Nintendo consoles.

Description
Players can post to Miiverse's Splatoon community from the mailbox in Inkopolis Plaza, either with text or a drawing, both of which are created on the GamePad. Drawings may appear as graffiti or on billboards in the Plaza and in various Stages, and both drawings and text posts appear over other Inklings in the plaza when approached. When zoomed in on or seen when examining another Inkling with, the player can "Yeah" a post by pressing.

Miiverse posts can be hidden via the Options screen. They will then be replaced by placeholder drawings, the source of which is unknown.

Splatfest
During Splatfest, many more Miiverse drawings can be seen around the Plaza. They adorn a variety of objects, including fireworks, neon signs, and the backs of the Squid Sisters' trucks.

Closing
Due to the Miiverse Shut down on November 7th, all miiverse post will no longer be present. Miiverse Graffiti will no longer appear in Inkopolis, and along with maps, such as Saltspray Rig, and Ancho-V Games. This goes with interacting with other Inklings as well. Normally if the user isn't connected to the Internet, other Inklings won't have any Miiverse posts present. When connected to the Internet, other Inklings will have Miiverse posts and if their drawings, they can be found as graffiti in Inkopolis. It's unsure if the Miiverse Box will be removed from Inkopolis.

Attempting to use Miiverse while it is closed, using the mailbox and trying to post something on miiverse will no longer work. The Wii U error message pops up and quotes,

"The Miiverse service has ended. Miiverse and any software features that make use of Miiverse will no longer be available"

It's unknown why Nintendo never removed the Mailbox from Inkopolis and can still be used, but the message blocks players from posting.

Octo Valley
Since Miiverse drawings are located in Saltspray Rig, The mission in Octo Valley Octoling Onslaught ~Rumble at the Rig~. Saltspray Rig has a few Miiverse post locations.

For a Strange reason, Miiverse drawings are still visible from the Neon Posters.

Trivia

 * Miiverse is split into three regions: North America, Europe and Oceania, and Japan. Players from one region will not see posts from another.
 * Miiverse posts can be un-yeahed by going into Miiverse.
 * Some, if not all, graffiti in Inkopolis Plaza is implied to be made by jellyfish; as stated in a developers' interview, jellyfish are known to create a large amount of graffiti.

Miiverse links

 * North America
 * Europe/Oceania
 * Japan