Billy Kid isn’t just one of the first Agents you meet in Zenless Zone Zero—he’s the kind of character who sticks with you, and not only because he wields twin revolvers named ‘the girls’ or geekes out over Starlight Knights with an almost childlike glee. Beneath that handsome cyborg exterior lies a personality that’s equal parts earnest sharpshooter and blushing anime enthusiast, and honestly… who wouldn’t want that on their team? To make sure he doesn’t just look the part but performs like a star, you need a build that leans into his long-range Physical damage and shores up his natural weaknesses.
By 2026, the meta has shifted more than a few times, but the core Billy build presented below has aged like a fine vintage—still devastating, still reliable, and still the go-to for players who want their dashing gunslinger to hit those Physical numbers like a freight train. Let’s break down every gear turn and stat tweak that turns Billy from a lovable dork into a top-tier Physical DPS.
The W-Engine: Starlight Engine Replica takes center stage
Not to be confused with the Starlight Engine, the Starlight Engine Replica feels almost custom-made for Billy—and given his obsession with the Starlight Knights, you could argue it’s fate. This A-rank W-Engine grants a whopping 36% increase to Physical damage on ranged basic attacks and dash attacks, which is essentially Billy’s bread and butter. The moment he starts unloading with ‘the girls,’ the Replica lights up, making every bullet hit like a mini explosion.
If RNG smiles on you and you manage to snag the S-rank Steel Cushion, swapping it in is a no-brainer. Not only does it stack an extra 25% damage on Physical attacks, but when Billy attacks enemies from behind, his attack climbs by another 35%. That’s a massive spike that rewards clever positioning—something a mobile gunslinger already enjoys. Still, for most Agents, the Starlight Engine Replica is the consistent workhorse; the Steel Cushion is the cherry on top for those lucky enough to grab it.
Drive Disks: Fanged Metal and Hormone Punk
Drive Disks are where Billy’s potential really takes off. The recommended combination is a 4-piece Fanged Metal set paired with a 2-piece Hormone Punk set, and the reasoning is as straightforward as it gets: Physical damage output first, attack second.
Fanged Metal is the set that resonates with the Physical attribute, and any boost to Billy’s natural damage type makes him immediately more lethal. The 4-piece bonus ramps up Physical damage in a way that feels like Billy finally gets to cut loose, peppering enemies from a distance while those damage numbers climb higher and higher.
Hormone Punk then steps in to fix Billy’s slightly underwhelming base attack. The 2-piece effect grants a clean 10% attack increase, and you know what? That little buff goes a long way. Billy’s base stats won’t set any records, so every extra point of attack from Drive Disks, sub-stats, and bonuses becomes precious. Whenever you’re stuck choosing between similar Drive Disks, always lean toward the one that pushes his attack further—let his revolvers do the talking.
Sub-stats and leveling priorities
When fine-tuning all six Drive Disks, the golden rule is attack first, with a side of crit rate and crit damage if you can get it. Billy’s kit rewards consistent Physical pressure, so you want his numbers to be reliable and chunky. The 4-piece Fanged Metal already amplifies the type damage, and Hormone Punk gives that base attack a leg up, but sub-stats that add extra attack % or flat attack turn decent volleys into lethal barrages. If you manage to weave in some crit, his back-attack synergy with Steel Cushion becomes even more lethal, though the humble Starlight Engine Replica doesn’t fall behind much.
Don’t forget the most basic investment of all: leveling Billy up. His base stats grow with each ascension, and a higher level means every percentage-based bonus from W-Engines and Drive Disks becomes more impactful. Think of it as Billy getting a little taller each time, and ‘the girls’ just hit harder because they’re proud of him.
Unlocking hidden talents and the power of duplicates
To squeeze every drop of performance from this build, you’ll want to unlock Billy’s six passive talents, and that means pulling duplicate copies from ZZZ banners. Each mindscape cinema level (as the game calls it) layers on improvements—better energy regen, longer buffs, or straight-up damage amplifiers that let him stay in the fight and keep those Physical numbers rolling.
Participating in the latest events, redeeming ZZZ codes, and keeping a healthy stash of Film for pulls aren’t just clichés—they’re the lifeline for an Agent you plan to use long-term. Billy Kid may be an early-game character, but his fan-favorite status means HoYoverse regularly gives players opportunities to snag duplicates, especially during rerun banners. By 2026, routines are well-established: grind event rewards, keep an eye on the in-game mail, and don’t sleep on those temporary shops. A few lucky pulls can turn Billy from a friend you bring along for sentimental reasons into an absolute powerhouse.
He’s also one of the few Agents who slots effortlessly into almost any team comp centered around Physical damage or Stun supports, so you never feel like you’re wasting resources. Pair him with a stunner who gives him room to breathe, and watch him gun down enemies with a grin that says, “Told you the Starlight Knights are the best.”
…well, maybe he does fangirl a little, but it’s adorable, and when the smoke clears, the only thing left to say is: that’s why you build Billy Kid.