Lightning Rod

The Lightning Rod is a Pre-Hardmode sentry summon weapon that summons a cloud similar to that of the Nimbus Rod. However, unlike the Nimbus Rod, the Lightning Rod's sentry fires lightning at nearby enemies. It is one of four of the Ancient Weapons, weapons that have a 1/1000 chance of dropping from any monster anywhere underground (except for the dungeon) after Skeletron has been defeated.