Newtron

"Newtron surprises Sonic again using optical camouflage to try and blast Sonic. He can also transform into a rocket and charge towards Sonic."

- Profile, Sonic the Hedgehog 4: Episode I website

The Newtron (メレオン) is an recurring enemy in the Sonic the Hedgehog series. They are chameleon-based Badnik models created by Dr. Eggman which first appeared in Sonic the Hedgehog (1991). Usually coming in two types, the Newtrons can camouflage themselves.

Appearance
Newtrons are based on chameleons. Newtrons have a head, a stripy tail and four white feet with three fingers. One of these fingers are backwards so the Newtrons can get an extra grip. They also have yellow eyes with small pupils and a brown and sharp parietal crest. Newtrons come in two color varieties: green and blue. The green variation has yellow eyes and the blue varitation has red eyes.

Newtrons in Sonic the Hedgehog 4: Episode I are more smooth and have detailed limbs. In Sonic Generations though, they are more mechanical and both varieties has cyan eyes. Newtrons in Sonic Lost World are slightly smaller than previous models and have cyan eyes with yellow sclera.

Powers and abilities
Newtrons can camouflage themselves accordingly to the wall they are on and phase out of sight when they see their target. They have also different methods of attack depending on their colors:
 * The green Newtron, after becoming visible, spits a ball of energy at the player before turning invisible again. It never moves from its wall though.
 * The blue Newtron, after becoming visible, drops from the wall and morphs into a chameleon-shaped rocket, which chases Sonic in a fixed horizontal line. The blue variety is easier to deal with as it can be attacked, unlike most of its green counterparts. Green Newtrons in Sonic the Hedgehog 4: Episode I however, are also able turn into rockets as well.

Sonic the Hedgehog (1991)
Newtrons make their first appearance in the original 16-bit version of Sonic the Hedgehog. Both varieties appear in the Green Hill Zone. Both of them can be destroyed with Spin Jump as they starts to appear on the wall. Green variants can shoot energy balls from the walls at Sonic, whereas blue variants will jump off the walls and attack the player directly. On some occasions, the player is unable to destroy green Newtrons depending on their placement in the Zone.

In 8-bit version of the game with same name, only the green variation of Newtrons appear at Jungle Zone, although they have the same attack patterns as their 16-bit counterpart. However Newtrons do not have Animals inside of them as power source like many other Badniks in the Master System and Game Gear titles.

Sonic the Hedgehog 2 (8-bit)
In the 8-bit version of Sonic the Hedgehog 2, the Newtrons appear in Under Ground Zone, Sky High Zone and Green Hills Zone, while being named as Meleons in Japanese manual. This game also has the two variations of Newtrons, although the green ones have the same color scheme as the rocket-types. Both types have the same attack patterns from previous game, although none of them contain Animals.

Sonic the Hedgehog 4
In Sonic the Hedgehog 4: Episode I, only the green variety of Newtrons appears in Splash Hill Zone. They keep their attack pattern from their first game and can also transforms themselves into a rocket which moves in a horizontal direction along the platforms.

Sonic Generations
In the Nintendo 3DS version of Sonic Generations, both blue and green Newtrons appear in Green Hill Act 1. Despite their redesign for the game, the Newtrons have the same attack pattern as in their first game and are placed in the exact same places. However, none of Newtrons contain Animals.

Sonic Lost World
In Sonic Lost World, the Newtrons regain their original design, although they are smaller. During the game, it turns out that the Badniks, the Newtrons included, got hijacked by the Deadly Six.

Green type Newtrons appear in Windy Hill Zone 1 and Sky Road Zone 1 in the Wii U version, and in Windy Hill Zone 1-2 in the Nintendo 3DS version. Green Newtrons mostly have the same attack patterns as in Sonic the Hedgehog (1991), as they turn invisible, hang on walls and shoot small projectiles at the player. These Badniks can be defeated by using the Focused Homing Attack. In this game, they again contain Animals inside of them.

Sonic the Hedgehog Story Comic
Newtron appears in Sonic the Hedgehog Story Comic manga. In the Sonic the Hedgehog Story Comic Volume 2' story ''Clash!! South Island'', Picky explains to Sonic that have Ricky and Cucky have trapped to the Badniks and so Sonic heads to the rescue. In Sparkling Zone, he suddenly confronts Newtron and Crabmeat who attempt to attack him. Sonic defeats them easily and finds Ricky and Cucky inside of them as organic batteries.

Sonic the Comic
Newtrons have appeared in several early issues of Sonic the Comic as standard members of Doctor Robotnik's Badnik army. Earlier models of Newtrons (which appears to based on the game appearance) appear to be weak and quadruped.

Later Newtron models have completely different patterns as they don't use projectile weapons nor cloaking ability, but simply attacked enemies with their claws, teeth and tails. These Newtrons also appear to stand on two legs. These Newtrons are more bipedal and serve as melee fighters of the Badnik army. However these models got decommissioned after the electromagnetic pulse, which affected the Mobius.

Archie Comics
In the Sonic the Hedgehog comic series and its spin-offs published by Archie Comics, the Newtron was one of the Classic Badniks created by Dr. Ivo Robotnik, though the model was eventually rendered obsolete by more advanced robots and got decommissioned. It did resurface during the events of Operation: Clean Sweep though.

After the events of the Super Genesis Wave, the Newtrons became nearly identical to their game counterparts.

Sonic X (comics)
In the Sonic X comic series published by Archie Comics, a rocket-type Newtron appears at the virtual reality version of Green Hill Zone, as it tries to attack on Sonic, who keeps wondering about the blue Shield around him that he has got from the Item Box.

Merchandise
The toy company TOMY has released Newtron action figurine during the release of Sonic & Knuckles as it also includes a series of 21 Sonic figurines and these figurines came in packs of four under the Sonic & Knuckles label and were also released individually under a Sonic the Hedgehog label.