Liquids

There are four: water, lava, honey and Shimmer. They run on one shared physics model and differ in speed, in what they do to you, and in what they make when they touch each other. Water is fastest, lava is slower and burns, honey barely moves and heals, and Shimmer is its own thing. Buckets handle the first three; Shimmer moves only by pump.

Liquid fills a tile fully or partially and spreads until it runs out of room. Moving liquid is drawn thicker than it sits at rest, so a fresh pour looks like more than you have. Loading a world runs a settle pass over everything still in motion, which is the loading step you watch before you drop in.

There is a floor to how thin liquid can get. Spread one bucket over a wide enough flat surface and it drops under the minimum and disappears, which is the cheapest way to delete a pool. The reverse also happens: falling liquid gains volume as it splits across tiles, and that gain underpins every duplication setup.

A bucket used on liquid checks a three by three area for more of the same and takes what it finds, up to one tile's worth. Even if it gathers a fraction, it fills completely and pours a full tile back out. That asymmetry is the whole of bucket duplication: pour into a small catch basin, scoop the same puddle back, and let the surplus run into storage.

Inlet and outlet pumps shift up to four tiles per pulse when wired and triggered. They cannot create liquid alone, but in a closed loop with a drop that splits the flow, the volume gain does it for them. Pumps win on big jobs; buckets beat laying wire for a small amount over a long distance.

You cannot place liquid into an occupied tile, and hammering a block into a half or slope does not open it up: liquid beside the empty half looks like it fills the gap but cannot be scooped out of it. Blocks go into water and honey but not lava, and liquid you cover this way is trapped and inert.

That trapping is temporary. On the next world load the settle pass behaves as though the covering block were not there: if a path to open space exists the liquid escapes, otherwise it is deleted. Walling liquid in is a slow way to destroy it.

A full tile of liquid next to a half block visually pours over the edge as a fall, and that fall is decoration. A lavafall will not burn you, a honeyfall will not heal you, and a Shimmerfall does nothing. Ceiling drips are the same, and you can place your own with the magic water dropper.

Two block types invert the rules. Bubbles stop liquid while letting you walk through, and Grates pass liquid while blocking entities.

You sink. There is no swimming by default, and liquid slows you in proportion to how slowly it flows, so water barely bothers you and honey nearly stops you. Falling into liquid cancels all fall damage regardless of depth, which makes one tile of water at the bottom of a shaft a safety net.

The flipper gives free movement in any direction but no buoyancy, so you sink the moment you stop. The inner tube holds you at the surface instead. Neptune's Shell covers water, honey and Shimmer, never lava. One detail that catches people mid fight: touching liquid does not reset wing flight or rocket boots.

Water and honey drown you; lava and Shimmer do not. Once your head goes under, a breath meter appears and empties, and at zero you take around 17 health per second until you surface. The diving helmet, diving gear and the two later sets slow the drain rather than stopping it, and the breathing reed stacks with them and refills your breath outright in shallow water. Only a gills potion removes the meter.

Contact between different liquids makes a block and consumes up to one tile of each. Water and lava give obsidian, water and honey give honey blocks, honey and lava give crispy honey blocks, and Shimmer against any of the three gives aetherium. Neither side needs a full tile, which is why one bucket converts several times its volume.

That reaction is also the fastest way to delete a liquid, at the cost of the one you pour in. Contact blocks do not form in front of furniture or actuated blocks, so a chest in the chamber lets one liquid eat the other and leave nothing.

Water, lava and honey each act as a minor crafting station nearby, and recipes never consume any.

• Sponges, one per liquid: Super Absorbant, Lava Absorbant and Honey Absorbant, plus the Ultra Absorbant combination at a Tinkerer's Workshop for all three and Shimmer.
• Dry bombs and dry rockets clear any liquid in an area, and the Cyborg sells the rockets.
• Freeze bombs from the Demolitionist convert water to ice, and nothing converts ice back.
• Pour in a little of an opposing liquid and let the reaction consume it.
• Give it a wide flat floor and let it thin out below the minimum depth.