The Asteron (テルスター,Terusutā?, lit. "Telstar") is a recurring in the Sonic the Hedgehog series. They are a hovering starfish-type Badnik models created by Dr. Eggman. Asterons are simply designed and are located usually on walls and are able to self-destruct and fire its five sharp parts in many directions.
Asteron has a simple, flat starfish-shaped appearance. Its core body is colored light-yellow and in the middle of the body is gray hole with red eye on the hole. All five sharp points have gray spears, that are pointing towards five directions. Asteron's appearance in Sonic the Hedgehog 4 is more detailed, even though involving only slight changes.
Sonic the Hedgehog 2
Asteron makes its debut in Sonic the Hedgehog 2, where it is one of the three deadly Badnik types featured at Metropolis Zone. These Badniks hide at walls, floors and ceilings, where they cannot be harmed. When approached, however, it will move closer to the player. They will then self-destruct, causing it to fire its star points, which are like spears, in five different directions. Its red eye helps it to detect the player when they are close enough.
In certain parts of Metropolis Zone, there are narrow vertical passages scaled by running up a screws on nuts, there are about four to six Asterons along the way. Their threat is increased as their spear attack can cause the player to fall off the nut, often requiring the player to move away to scroll the screw off-screen to reset the nut at the bottom.
In the 2013 re-release of the game, a couple of Asterons are present at the beginning of the Metropolis Zone segment in Boss Attack Zone.
Sonic the Hedgehog Pocket Adventure
Asteron Badniks make their next appearance in Sonic the Hedgehog Pocket Adventure, where they are featured at Gigantic Angel Zone. As Gigantic Angel has many identical gimmicks and elements from Metropolis Zone, it has also the same Badnik models with similar attack patterns. However Asterons are seen hovering in the air and the player is able to destroy these Badniks before its self-destruction, thus freeing the animal inside of it. Asteron Badniks also are seen flashing red before its exploding.
Sonic the Hedgehog 4: Episode I
Asteron make a reappearance in Sonic the Hedgehog 4: Episode I, with a slightly different design. They are featured at Mad Gear Zone, which again has the same Badniks. Despite that, these Badniks retain identical patterns from previous appearances, but the player is once again not able to destroy these Badniks. In this game, before their self-destruction, these Badniks spin around.
In gameplay, Strange Relief-based obstacles will periodically fire sideways-aligned Asterons into walls. Because of the sideway view of them though, these Asterons appear as first glance as simple spears. Touching these Asterons while they are in flight will damage the playable characters. If these Asterons are allowed to hit the walls however, they can be used as platforms by the player for a few seconds before they fall off.
During the boss battle with the Heavy Shinobi, the Asterons are used as shurikens by the aforementioned Hard Boiled Heavy when he jumps. At first, he throws only one Asteron at a time, but the more damage he takes, the more Asterons he will throw at once, with three being his maximum. When they are thrown into the wall or floor, the player can use the Spin Jump to destroy them. Leave them alone for too long however, and they will start flashing before detonating and releasing damage-inducing spikes in five different directions.
Powers and abilities
All Asterons have the ability to levitate in midair. As their main offense, they self-detonate themselves, causing them to release deadly spikes in five different directions.
In the Debug Mode of Sonic the Hedgehog 2, it is possible to destroy Asteron Badniks simply by Spin Jumping on them and freeing animals inside them if these Badniks are not set on to walls. Because the original game does not let the player to have the chance to destroy these Badniks, animals inside them are apparently killed after the Badnik's activation and self-destruction. However, it is likely that the animals inside Asteron Badniks are non-canon.
Asteron and Crawl are the only Badniks in Sonic the Hedgehog 4 that are not featured in the game's website.