Oil
Oil is the lightest liquid in Sandlab: it floats on water and acid and catches fire readily.
- Movement
- Liquid — flows and levels out
- Weight
- 2 / 9 (heavier sinks through lighter)
- Lifetime
- Permanent
- Glow
- None
Oil has weight 2 against water’s 3, so water or acid beneath it stays beneath, and oil poured into a full tank spreads into a thin film over the top. By the same rule every powder falls through it. Only the gases, at weight 1, are lighter.
Real oil floats for much the same reason: it is less dense than water and does not mix with it. Sandlab captures that with a single weight comparison. It does not model viscosity, though, so oil runs just as freely as water here, whereas a real heavy oil would ooze.
Oil burns at 50 percent per check from both directions: oil’s entry turns it into fire when a flame touches it, and the flame’s entry converts neighbouring oil as well. The original flame survives each ignition. That rate sits between plant and gunpowder, so a slick catches as a fast sweep across its surface rather than a single flash.
Lava lights it at 80 percent from the oil side and 70 percent from the lava side, and the lava stays lava. Being much heavier, lava sinks straight through an oil layer and ignites the oil it passes on the way down.
A burning film on water is stubborn. Water poured onto it is heavier than the oil, so it drops through the fuel, quenching only the flames it happens to hit, and ends up underneath while the oil keeps burning on top.
Try it yourself
- Burning bridge. Fill a wide basin with water, pour a thin layer of oil over it and light one end. The flame sweeps across the surface; once the oil is gone the fire stops, with only a little of the water below lost to steam where flames brushed against it.
- Three liquids in a tube. Pour water, then oil, then acid into a narrow wall tube. The oil finishes on top, while the acid passes below it and meets the water; because those two are equal in weight they do not stack, and they turn to steam where they touch.
- Lava through a slick. Pour lava onto a pool of oil. The lava sinks, lighting the oil along its path, and comes to rest on the floor glowing beneath a sheet of flame.
Reactions
Odds are per contact check: each tick, touching cells inside the same two-by-two block are checked against the reaction table, so even a small chance happens soon after contact.
When oil touches something
- Touching Fire: turns into Fire. (fast, 50% per contact check) →
- Touching Lava: turns into Fire. (almost instant, 80% per contact check) →
When something touches oil
- Touching Lava: this Oil turns into Fire. (almost instant, 70% per contact check) →
- Touching Fire: this Oil turns into Fire. (fast, 50% per contact check) →
Tip
A thin film of oil lets fire cross a pool, which otherwise works as a natural firebreak.