World mechanic
Water freezing
Water open to the sky in a cold place turns into Ice when it is dimly lit and has at least one side that is not water; no snowfall is needed.
Rules
| Temperature | The temperature at the spot must be below 0.15. |
| Light | Block light must be below 10. Sky light does not count. |
| Water type | Only a water source block freezes. Flowing water and waterlogged blocks do not. |
| Edges | At least one of the four blocks beside the water must hold no water, so a lake freezes from its edges inward. |
| Open water | Only the highest block of a column can freeze, so water with a solid block above it stays liquid. |
| Weather | No rain or snowfall is needed. |
