Gatehouse engine
The Chain
The The Chain is a gatehouse engine in Marrow March. An iron chain strung between two facing bastions. It stops the road dead — until the weight on it snaps it, and the snap whips through them.
| Kind | Gatehouse engine |
|---|---|
| Does | Holds, then snaps |
| Opens | once the first age is cleared |
| Goes | on the road behind the wall, to hold it after a breach |