It’s super fast, just about as fast as moving as a squid in your ink. And it says the Ink Brush doesn’t do much damage. Well, I strongly disagree. I can’t tell you how many times I’ve been killed by an Ink brush with just two swipes of the thing, and the people that killed me didn’t even have offence up abilities. And it’s hard to escape because the swipe has such a wide range and it splatters ink towards you which also hurts you.
Were you already damaged (just got out of a firefight, standing in enemy ink for a while, etc.)? Were they swinging at you earlier and you only noticed the last couple swings? Because it really isn't that strong, though it can be swung really fast. I think it's a 4-5 hit splat (think it might be 4, I just get 5 because I miss and/or they have Defense Ups). Also, its swing has so little range, I think Aerosprays might be able to outrange it (or at least it feels that way when I use it), and the Sprinkler doesn't help with splats at all (again, just my experience). Also, I feel like it eats through ink fairly quickly (but I could be doing it wrong).
Still, it IS pretty great for covering areas, given the speedy, wide swings, speedy movement and Sprinkler and Inkstrike to cover areas, so yeah, it can certainly feel OP in some areas, but it has rather pronounced weaknesses too.
The Inkbrush is like Little Mac in Super Smash Bros 4; powerful in its element (close range combat, covering flat and flat-ish areas quickly, Sprinkler-ing), but it has clear areas in which it suffers (ranged combat, like any ranged combat, also shooting vertically).
