Caterkiller/Pre-SGW

Caterkiller is a caterpillar-based badnik created by Dr. Ivo Robotnik and later by Dr. Eggman during the reset world created by the Genesis Wave. It is distinguished by its numerous spiked segments that can detach from each other with ease. It appeared to be a high ranking badnik on the Island of Misfit Badniks.

Early Battles
Caterkiller was the very first badnik to fight Sonic the Hedgehog, attempting to block Sonic's path before being hit by a wave of Mega-Muck which segmented him. (OSM: #0)

He was seen in a crowd scene for badniks at Casino Night Zone, was part of an ambush on a wedding between Sonic and Princess Sally, before it was discovered that it was just a play, and becoming the first badnik to fight Sonic at the Robo-Hobo Jungle, with Sonic pointing out that Caterkiller was the first badnik he encountered. Sonic managed to get some information regarding Nack the Weasel from Caterkiller after segmenting Caterkiller again and threatening to drag his head against the ground at high speed. (StH: #1, #18, #40)

Super Model
A significantly larger train-based Caterkiller was unleashed by Dr. Eggman for the task of terrorizing numerous towns by plowing through them. This version of Caterkiller plowed through Furville before heading for Knothole Village. Sonic was able to phase himself and Tails through the armor so that Tails could reprogram it to run off a cliff and into the sea. The Caterkiller took all of its segments with it this time. (StH: #119)

Later Fights
When Sonic decided to investigate the Island of Misfit Badniks, Caterkiller and numerous other badniks ambushed him. Sonic quickly beat them segmented Caterkiller again, before Pseudo Sonic emerged. There fight between them resulted in the island sinking. Caterkiller, referred to as a Commodore, watched Sonic dash away, completely oblivious to the badniks' survival. He promised that they would meet again soon. (StH: #170)

Their revenge scheme of enlarging Pseudo Sonic was interrupted by the Forty Fathom Freedom Fighters, who kept smashing badniks trying to stop them. Caterkiller led the last wave consisting of Jaws, Bat Brain, and Buzzbomber to combat them. Caterkiller was able to wrap himself around Ray before Pseudo Sonic knocked them all away with his giant hand. Big Fluke then crushed Pseudo Sonic, the badniks, and Caterkiller's head and segments, into a cube. (StH: #185)

Appearing During Genesis
At least two Caterkillers reappeared in Marble Zone during the events of Genesis, but this time they were created by Dr. Eggman. One Caterkiller attacked Sonic and Sally, but Boomer snatched the robot, twisted its bolts, and slammed them back into it, causing it to explode. Another Caterkiller was later seen being destroyed by a reprogrammed Buzzbomber. (StH: #226)

Abilities
As a caterpillar-based badnik, its numerous segments can be used to hit opponents. Its length, varying from issue to issue, can be used to its advantage as the far end is likely moving the fastest, and there is a chance of wrapping itself around its opponent as Ray learned. Fortunately, the segments detach with little force.

As a train-based badnik, it has many segments, nigh indestructible armor, and great speed. It appears to be capable of plowing through cities, but not much else. It has significantly less intelligence than the smaller bog-based badnik, as a simple computer with no manner of A.I. runs the whole robot.

Background Information

 * Caterkiller is based on the badnik from multiple Sonic games. In Sonic the Hedgehog, Caterkiller (known as "Nal" in Japan), appeared in the Marble Zone (Genesis only) and the Scrap Brain Zone (both Genesis and Game Gear) and consisted of only 4 segments, including the head. The color scheme used in the Genesis version was Caterkiller's color scheme in the comics (Game Gear had a pink Caterkiller). A blue variation appeared in Sonic and Knuckles in the Sandopolis Zone, and another grey variation with a purple head appeared in the Green Grove Zone in Sonic Blast. In all versions, the head is the only point that can be attacked safely, though the spikes cause no trouble in the comics. Like the comics, the original Caterkiller is known to see its segments scatter, but only if attacked wrong.
 * Writer Karl Bollers revealed that one of the long scrapped plots would have have A.D.A.M. reactivate Caterkiller (the train version), as part of his rebellion against Dr. Eggman. Though A.D.A.M. did rebel (for different reasons than planned), Caterkiller is likely still underwater, assuming the Forty Fathom Freedom Fighters didn't do anything about it.
 * Caterkiller's train design shares a resemblance to the Egg Carrier's transport vehicles in Sonic Adventure for Dreamcast.
 * Giant Caterkillers with a different design were used by an alternative dimensional version of Dr. Eggman, whilst he was trying to usurp the Olympic games in #242, they also had the ability to fire lasers from their heads.