You cannot apply two copies of one oil, but there are several oils with the same stat: Great Oil and Heavy Oil (+60% damage each), Glass Cannon Oil and Slow Punch Oil (+50%), Hyper Lead Oil (+40%) and more. Whether the third or fourth of them is worth its slot depends on a rule SULFUR has not documented: do percentage bonuses on one stat add together or multiply? The community calculators add them, and so do our records. Under that rule each extra damage oil is worth less than the one before.
Five percentage damage oils, one after another
| Oil added | Its bonus | Total if added together | Gain from this oil (added) | Total if multiplied | Gain (multiplied) |
|---|---|---|---|---|---|
| 1. Great Oil | +60% | +60% | +60% | +60% | +60% |
| 2. Heavy Oil | +60% | +120% | +37.5% | +156% | +60% |
| 3. Glass Cannon Oil | +50% | +170% | +22.73% | +284% | +50% |
| 4. Slow Punch Oil | +50% | +220% | +18.52% | +476% | +50% |
| 5. Hyper Lead Oil | +40% | +260% | +12.5% | +706.4% | +40% |
Added together, five damage oils reach +260%, and the fifth raises damage by only 12.5%. If they multiplied, every oil would add its full value and the same five would reach +706%. The difference is too large to miss in game: a 60-damage pistol with those five oils would show 216 damage per bullet if they add and 484 if they multiply.
Why the best builds use projectile oils
Projectile oils (Bombard, Careless Splitter, Matrix, Suppressive and others) change a different stat, the projectile count, which has its own percentage pool. Under additive stacking a +200% projectile oil triples the projectiles even when the damage pool is already full, while its damage penalty only shrinks a large pool slightly. That is why the optimiser fills slots with two percentage damage oils and then projectile and fire-rate oils:
In the best five-oil set of each of the 54 guns (aiming kept, stock spread): 26 guns use 1 percentage-damage oil, 28 guns use 2 percentage-damage oils; 54 sets include at least one projectile oil.
The extra projectiles come with large spread penalties. The best oils record shows both the uncapped sets and the sets that keep the stock spread.
Using this
- Two damage oils, then something else: once +100% or more of percentage damage is on a gun, a flat oil, an RPM oil or a projectile oil usually adds more than a third damage oil.
- Spread the bonuses over different stats. Damage, projectiles and RPM each have their own pool, so +60% on each multiplies; +60% three times on damage does not.
- Because this depends on an unconfirmed rule, the build calculator has a switch between adding and multiplying.
Sources
- SULFUR Wiki: Oils (revised 30 October 2026)Oil cards and the flat-before-percentage rule; the page does not say whether percentages add or multiply.
- SULFUR Wiki: Enchantments (revised 2 November 2026)Only one of each oil, slots up to five.
- Shocco/sulfur-calculator (GitHub, November 2026)Community calculator that sums percentage modifiers (its PercentAdd type).
