Feed The Beast Wiki
Elder Eye

ModUpgrade Aquatic
TypeTile entity
Blast resistance1

The Elder Eye is a block added by Upgrade Aquatic. It always drops from Elder Guardians. Elder Eyes can be placed in any direction and underwater. When any entity (except Paintings and Item Frames) is within 15 blocks of where it is facing, it will create a strong redstone signal from all sides. Right click the Eye to toggle it on or off.

The Elder Eye detecting a Villager and providing the Redstone signal to turn the Redstone Lamp on.