Some leaves
Leaves make up the foliage of trees and can be found on newly generated maps. Players sometimes use this block for making tree houses, and it was also used as a glass replacement in pre-glass times. As leaves are partially see-through, the block allows light to shine through it. It is not affected by gravity.
In Survival Mode, players cannot place leaves. When destroyed, leaves sometimes drop saplings. In indev and infdev, when a tree's trunk is chopped down, the leaves that aren't resting on other blocks start to disappear, sometimes dropping saplings as they go.
In the Playtest, leaves that are hit on the top by direct sunlight changes the sunlight underneath them from 9 to 4. Leaves are also very flammable.