Probe

The Probe is a Hardmode enemy which spawns from one of The Destroyer's red lit segments. It fires lasers both from inside the Destroyer and detached from its master. It can pass through blocks, but its lasers can't.

Probes will only detach from The Destroyer after it has taken a fair amount of damage.

Probes make fighting The Destroyer a much easier and harder task at the same time; the hearts they drop will keep you alive, but their high damage can kill you rather quickly.

Tips

 * Probes are fairly small, fast, flying enemies who can deal consistent damage in a moderate amount of time. As such, most melee weapons are not recommended. Some good ways to defeat them are to use some ranged weapons such as a repeater or Minishark. Any fast firing weapon such as the Crystal Storm will do. These types of weapons allow the player to kill the Probes as well as being able to deal damage to The Destroyer.
 * It helps to use a Gravitation Potion or Rocket Boots/Spectre Boots/Lightning Boots/Frostspark Boots. These allow easy movement to dodge the Probes as they come towards the player and to dodge the lasers.