Assassin probes were assassin droids used during the Clone Wars. They resembled large spiders with eight spindly legs and multiple red photoreceptors.
An assassin probe attacks Duchess Satine's dinner party.
Around 22 BBY, three of these droids were used to attack the Duchess Satine Kryze aboard the Coronet. They were smuggled aboard by Senator Tal Merrik. During that incident, two of the droids attacked and killed the two clones guarding the cargo bay while the third remained hidden. One attempted to deceive General Skywalker by hiding behind the dead body of Redeye, but was discovered and had two of its legs sliced off, then was shot repeatedly by clone troopers. The second droid escaped up the turbolift shaft and was dispatched by Obi-Wan Kenobi. Both droids, after being destroyed, launched dozens of small probe killer droids through pits on their heads. The third droid released the probe killer droids while still hidden, then attacked Captain Rex, but was dispatched after Skywalker cut off its legs with a lightsaber throw and Rex had unloaded several blaster pistol rounds into the pits on its head.