The Nintendo UK Twitter account has given a glimpse of the new weapon that will arrive in Splatoon tonight for North America, and tomorrow morning for Europe. The new weapon is the Rapid Blaster Pro, which is based on the original Rapid Blaster but has an increased range. Its sub weapon is the Seeker, and the special weapon is the Inkzooka.
There will also be a patch update coming to Splatoon on October 20th. The update to version 2.2.0 will bring changes to weapons and sub weapons, ranked battle adjustments, and an adjusted ranking method – you can check out the full patch notes detailing changes arriving in the new update here.