Driller

Drillers are a race of non-sapient Cybertronic tentacle monsters and the largest subterranean lifeforms native to the planet Cybertron.

Anatomy
The Driller resembles a giant mechanical snake or worm and is armed with several tendrils tipped with saws and pinchers. Due to their fossorial lifestyle their heads are drill-shaped, hence their name.

Powers and abilities
Through the use of their tentacles and drill-shaped heads, Drillers are capable of burrowing through the ground or through buildings with ease. Ultimately, they are capable of great destruction and carnage on any scale.

Behavior
While Drillers are typically wild Cybertonian animals, they can be tamed and domesticated, as seen with the one Shockwave owned which was partially reengineered into his chariot and behaved like a loyal dog to him.

Transformers: Foundation
A Driller was drawn to the surface by the fresh energy flowing through the planet after Sentinel Prime's Autobots revitalized Cybertron by re-energizing the AllSpark. At the outskirts of Thetacon, it attacked some Hatchlings and their protector Starscream. Megatron and Shockwave saved them from the creature, forcing it into retreat, but the beast had left an impression upon Shockwave, who deemed it "magnificent".

Transformers: Rising Storm
At some point in the past, Shockwave captured and tamed a Driller. It was brought to Earth with him, and contained in a cage built by Astrotrain. When its master was about to get killed by Optimus Prime during the Decepticons' invasion of Philadelphia, the Driller suddenly showed up and saved him. Ironhide recognized the creature and told Prime that if the Driller is what he thought it was, then they were in a big trouble.

Transformers: Dark of the Moon
The Driller was summoned alongside its master to attack Optimus Prime when NEST was called to Chernobyl by Alexi Voskhod. This was only misdirection, to ensure that the Autobots did not realize that the Decepticons actually wanted them to find the fuel cell from the Ark located within the facility. After Optimus retrieved the fuel cell from the Driller, it quickly retreated underground. The experience left Optimus somewhat shaken, and angry with the humans that they had concealed the Ark from the Autobots.

Later on, the Driller was present in Chicago during the Decepticon invasion, proving to be a deadly threat from below as it separated Optimus from his trailer. It crawled its way in and through a toppling skyscraper by Shockwave's command to flush out Sam Witwicky and several former NEST operatives led by Robert Epps, causing the building to snap in half by having the top section slam onto another building. When the Driller went in to finish the humans, Optimus attacked it in midair using the jet pack and upgraded weapons from his trailer. The Driller's reach with its tentacles was hindered by the building as it attempted to fight back. Optimus counterattacked it by slamming his entire body through its neck, killing it. Its partially severed body crashed to the street below.

Transformers: Age of Extinction
Five years after the Battle of Chicago, the Driller was listed as "deceased" by the CIA taskforce Cemetery Wind. Though Brains stated that the remains of Decepticons killed in Chicago were recovered by KSI and melted into Transformium to be used for their man-made Transformers, it is unlikely that this applies to the Driller due to being a non-transforming Cybertronian lifeform.