Environment. Playable only if Doors of Night is in play. Each moving company with a Wilderness in its site path must return to its site of origin. Cannot be duplicated.
Another good feature of this card is that it CANNOT be bypassed. There's no way to get out of it, it's automatically there. This card is especially useful if used in conjunction with other cards. In addition to The Will of Sauron, you can also use it with Siege (to have a continuous attack on the company), Nazgul (if they're at a Dark-hold and you have lots of them in your hand), and Havens (if you're at a haven, you can keep doing stuff while your opponent waits (especially if you're at Grey Havens which is the only haven not fenced in by wilderness).
The only bad feature, as mentioned before, is that it also effects you. This can be easily avoided with planning, as described above. So overall, this is a great card, well worth having in your deck (especially if you have Will of Sauron).
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