In Stardust Speedway, Hotarus fly around in pars for a short while before locking themselves into position above and below on the screen when the player approaches. They situate themselves in such a way that no matter how the player moves, they stay in the same position in relation to the player. They then shoot a line of electrified balls in between them before flying away, never to be seen again. The player can destroy them with a Spin Jump before this happens. In the Bad Future or sometimes the present timeframe of Stardust Speedway, these Badniks will be worn down from age, showing broken light bulbs. Their attacks can also not harm Sonic and are more akin to harmless flashes.
In Metallic Madness Zone 3 there are three Hotarus in a closed room immediately before the final boss. As they each start appearing, they fly in linear direction, shoot an electrical laser straight down to the ground, and then fly to a different part in the room to repeat the pattern. The player is required to defeat the three Hotarus in order to reach the boss. These Hotarus are always present in this room, even in the Good Future for Zone which would ordinarily remove the enemies.
Within Stardust Speedway Zone Act 1 and 2 themselves, Hotarus pursue and abandon the player like they did in Sonic the Hedgehog CD, but their attack patterns have been changed; rather than appearing pairs, Hotarus appear here alone and will attack by shooting an electrical laser straight into the ground.
For the mini-boss of Stardust Speedway Zone, the player goes up against a Hotaru Hi-Watt, which is basically an larger Hotaru. When this boss flies off-screen during the battle, the player must then fight regular Hotarus. These Badniks comes in two waves based on their attack patterns: the first includes one Hotaru who behaves much like those faced throughout Stardust Speedway Zone Act 1, and the second includes a pair of Hotarus which appear high above the player and form a chain of electrical chain between them, before lowering themselves and the chain to damage the player. The latter wave's chain can be broken by destroying one of the Hotarus however.
Upon destroying a Hotaru in this game, it will release an Animal.
Powers and abilities
Hotarus are capable of flight and can move at speeds rivalling Sonic's. With the aid of their bulbs, they can emit electrical lasers, which they can either fire as beams or form electrical chains with when linking together with another Hotaru. Hotarus also have the ability to join together with other Hotarus to form a Hotaru Hi-Watt.
The Hotaru Hi-Watt is a giant version of the regular Hotaru. In additon to being able to fire larger laser beams, the Hotaru Hi-Watt can assemble itself from regular Hotarus or split itself back into them.
Hotarus in Metallic Madness Zone 3 are first notable enemies, that are required to be destroyed in order to pass through the room or proceed in the Stage. This game mechanic is utilized much later in games such as Sonic Heroes, Sonic Rush and Sonic the Hedgehog (2006), where some groups of enemies have to be defeated in order to open the door of the closed room or activate certain item separately or inside the Case.
↑While not listed in any instruction manuals, 1996 PC release of Sonic the Hedgehog CD refers to this Badnik either as "hotaru7" or "hotaru8" in the game's source code; the 7 or 8 designating which Round's version of the Badnik is being used.