Throw eyes from the Ender until one of them heads down. If an eye of the Ender floats to the ground, you are close to an underground fort. If the eye is moving backwards, in the direction you are coming from, you have passed the fort.
Throw eyes from the Ender until one of them heads down. If an eye of the Ender floats to the ground, you are close to an underground fort. If the eye is moving backwards, in the direction you are coming from, you have passed the fort.