Not four days after the game's release, Nintendo has confirmed the first bit of free post-launch content for Splatoon, and it goes live early in the hours of tomorrow.

A brand new weapon based on Nintendo's classic NES Zapper - appropriately named the N-ZAP '85 - will be made available. It's not the most powerful, but its rapid fire rate will make it a useful friend in the tighter maps.

And speaking of maps, a brand new one also joins the fray. Port Mackrel is unique for basing the fighting on top of and around a whole bunch of cargo crates. Will you go for the higher ground? Or maze your way through the enemy territory?

Finally, and perhaps the most significant in terms of the game's longevity, is the arrival of ranked battles. You'll need to be at least level 10 to access these. Ranked battles open up Splatoon to a brand new game mode aside from Turf Wars. Splat Zones will have teams duke it out for control of specific areas on the map.

Splatoon launched worldwide last week, and is by all indications doing very well. Earlier today, it was confirmed as the fifth fastest-selling Wii U game in the UK.