Brushes are a very abusive class, and take their abilities for granted a lot. They function very similarly to rollers but minus the vertical flick. Pressing zr with a brush makes is swipe once to the left, and if you spam zr, you will swing it left and right. Holding down zr goes into a "rolling" mode where you gain tons of mobility, but don't cover much turf. They typically take advantage of their great mobility to flank the other team. They are also great at luring them away from key areas. The brush's weapon roles vary between weapons, but they all are known for being half slayer half skirmisher. They typically excel at being a pest to the other team and are usually the biggest target. But taking advantage of this is a great way to play brushes, and is mainly what you must focus on doing. You could also go the support route and cover turf if you want. Luckily, brushes also excel at that too.
Inkbrush is a very, very speedy weapon in many literal terms. Its "fire rate" is really fast and great at killing. Similar to a roller, by holding ZR then you will put the weapon flat on the ground, but this time makes you very fast but it can't kill or cover turf at all. Inkbrush has splat bomb and Killer Wail 5.1 which are decent on it, and both have their perks for the weapon. Splat Bomb is good at leading pushes and clearing the way so you can get in, while Killer Wail is good at chasing far-off ranged opponents and getting cheap kills. Sharking is a great way to get by with this weapon, just be sure to combine splat bombs into the mix of attacks.
-Max
It's got a decent kit, with ink mine, and ultra stamp. It's pretty aggressive and supportive, but I like the OG better. It still has ultra stamp, so use it to get turf covered. This weapon is also great at starting and preventing rushes, so abuse this to the max.
-Max
Octobrush is still decently fast, but a bit slower than the inkbrush but a bit stronger. This weapon can cover turf and kill pretty well, and with suction bomb and zipcaster, I believe my point has been proven. Suction bomb is okay at covering turf but is pretty useful at killing, meanwhile, zipcaster is great at doing both due to how you can unexpectedly zip to somebody and kill them, or get really far into their base and cover turf. This weapon is a mixture of all of the brushes, minus all of the downsides, making it a very good brush at doing almost anything, which is why it is the best brush.
-Max
Octobrush nouveau is weird. Its kit doesn't do much in the battle and is mainly useful for support. Its kit is squid beakon and ink storm. I don't like its kit much, so I'd use the original octobrush if I were you.
-Max
Painbrush is the slowest of the brushes but is also the strongest. It can kill within 2-3 hits depending on the distance you are from the enemy. This weapon has the most range out of all the brushes so it can handle some weapons more easily. If a Painbrush can get up high above everybody, then you are almost guaranteed to be killed instantly by it. Its kit is Curling Bomb and Wave Breaker, which is just okay. Its not amazing, and doesn't work too well, so don't rely on it.
-Max
Painbrush nouveau is exactly the same as the painbrush, but it has point sensor and tenta missiles, both allowing you to see where people are. This weapon is slightly less aggressive than the normal painbrush, being more of a support weapon, and could go well with a brella or shooter.
-Max