Anchors, sometimes known as bonds, nails or hinges (although the map editor labels them as nails) are the link physical items to the stage and to other items. Anchors linked items spawn with the map, or can be attached to items by the shaman to assist in building.
There are five different types of anchors available for use. Newer shamans usually have a tough time with anchors. The only way to create anchors is through the C, V, B, J or N keys. Pressing a key multiple times will move the anchor from the center to either side of the object, except in the case of the red nail, which may only be attached by the middle. In the case of balloons, pressing any anchor hotkeys will allow the shaman to connect the balloon to another object with a string.
Can be attached directly to the stage or to another item.
Can only be used with planks.
Useful for providing a base for other attachments.
Can be attached to the air "through" another item, allowing it to turn in the air, or locking it there if it cannot turn (anchored, or touches the ground etc.)
Cannot be used in Hard Mode (unless in a Totem) or Divine Mode.
Automatically creates a string between a balloon making the balloon lift the item.
Used for making airships or stabilizing and elevating bridges.
The key used makes no difference.
To connect a balloon to a mouse, the circle that is the nail must be at the body of the mouse for it to work.
Overlapping anchor
To add an anchor onto overlapping things, like the ends of anvils, select the arrow shaman item and the anchor of your choosing. Once you place the arrow where you would like the anchor, the arrow will disappear and leave the anchor behind.
Note: This doesn't work with a red anchor.
Anchor to anchor
If you add a item to another item with a blue anchor, for example a long board anchored to a short board that is held in place by a red anchor, you can do an arrow nail with a rotating anchor or a lime anchor to make it move or stop moving.
Note: You can do this as many times as you want.
Trivia
Despite the free anchor commonly being called "blue", the game refers to it as green in the map editor.
This also happened with the solid anchor commonly being called "green", The game refers to it as yellow in the map editor.