You make three choices in a run, at levels 15, 30 and 45, and they're permanent. The in-game panel shows you a silhouette and a name, which isn't enough to choose well the first time. This page says what each branch is actually for.
Every class here has its own name. surgio isn't a reskin with borrowed labels, so a Shepherd is a Shepherd and what it does is written out below rather than assumed.
You start as a Recruit with one barrel and no identity. At 15 you pick a direction. This choice matters less than people think, because every branch leads somewhere strong. What it really decides is how you'll be farming for the next five minutes.
| Class | What changes | Take it if |
|---|---|---|
| Duet | Two barrels that alternate. Roughly double the shots, each a bit weaker. | You want the safest, most forgiving farming. |
| Vantage | One heavy, fast, long-range shot and a wider view. | You'd rather hit hard from outside trouble than trade up close. |
| Rattler | A fast spraying stream with spread. | You like close-range pressure and can accept missing a lot. |
| Rearguard | A forward barrel plus one firing backwards. | You want mobility. The body is faster, and the rear barrel cancels your recoil. |
Rearguard's back barrel isn't a thruster. Both barrels fire together and their kicks cancel out, so a Rearguard never gets pushed around by its own shots and can hold fire while it chases at full speed. The forward push comes one tier later, from Vector's angled rear barrels. If something has ever run you down that shouldn't have caught you, that was why.
This is the volume branch. Trident concentrates forward. Crossfire and Quadrant spread coverage around you. Quadrant fires on all four sides, which sounds strong but mostly means you're never pointing your full damage at anyone. Take it to farm and survive, not to duel.
This is the widest branch in the game and the most interesting.
Volley tightens the spray into something you can aim. Buckshot goes the other way: it's a real shotgun, one fat barrel throwing six pellets per shot into a short-range cone. Buckshot is genuinely dangerous inside its range and close to useless outside it, so it's better in team modes where fights happen in tighter space. And if you skip tier 3 and stay a Rattler, you can take Deluge straight away at level 45.
Vector is the mobility payoff. It's fast, awkward to hit, and it's what the ramming builds are based on. Triad Sentry goes the opposite way. It swaps your barrels for three auto-aiming turrets on its rim that fire on their own while you drive. There's no manual gun at all.
By now you're committed, and the final tier mostly deepens what you already are. A few worth knowing about:
Eight classes command drones instead of firing bullets: Shepherd, Hivelord, Steward, Revenant, Foundry, Snarelord, Dreadnought and one hybrid. They play differently enough that trying one blind usually goes badly.
The swarm follows your aim while you hold fire. When you let go, any drone with something to hit within 400 px goes and attacks it, and the rest come home and orbit you. That's the whole control scheme. It also means letting go is a real move, because it brings your idle drones back to defend you. If you hold fire permanently you're flying your entire defence to the far side of the screen and then wondering why you died.
Drone classes get a second ability that pushes the swarm outward instead of pulling it in. Used right it's a wall between you and something charging you. Used wrong it scatters your damage. Use it when something fast has already committed to closing.