The golden rings featured in nearly every Sonic game are one of the series' most recognizable features. Found everywhere from outer space to deep underground, in pocket universes and the core of the Internet, these golden hoops are of great and varied utility to Sonic and friends.
While they usually act first and foremost as a sort of shield against damage, rings' uses are many and varied, and their precise role in gameplay varies from title to title.
By far the most recognizable and prevalent attribute rings display is their function staving off loss of lives. In general, the rings a character holds prevents them from dying when hit by the spikes or claws or kill-bolts of foes. If an (unshielded) character is hit by an enemy and is holding rings, he drops the rings and is usually rendered flickering and invincible for a short period. Being hit with no rings in pocket, on the other hand, will cause the character's death. The rings' one weakness is to stop turning, and that was makes them disappear. However, it is impossible to get exactly all your rings, unless you have a few (1-3 rings).
In the great majority of Sonic games, a hit causes the character to drop all their rings, regardless of how many they are holding in total. There are exceptions, however: for example, 50% of rings are dropped when hit in Sonic Unleashed (provided you have 40 or more); a set loss of 10 rings occurs in some games such as Sonic Blast and Shadow the Hedgehog; while Tails loses varying numbers depending on the severity of the hit in Tails Adventures.
Rings also serve as fuel for characters' super transformations. In the older games, one of the conditions for attaining Super Sonic was to collect 50 rings and tap jump twice. Once in his golden form, Sonic's ring count falls steadily, and he reverts to his normal blue self once it reaches zero. The decreasing ring count is a general feature across many player-controlled super forms, including the Hyper transformations and Burning Blaze.
The great ubiquity of the rings as the series' generic 'collectible item' has seen them serve a variety of additional minor purposes over the years, including:
- Extra Lives: Originally, Sonic received an extra life for getting 100 rings, and another extra life for 200 rings. In later games, extra lives are also awarded at 300, 400 and further multiples. However, in Sonic Unleashed, only the first 100 rings provide an extra life, and even then, only in the PS3/XBOX 360 version.
- Currency: From Sonic Adventure onwards, characters have frequently been able to exchange rings for items in various overworld boutiques. Rings functioned as slot-machine prizes as far back as Casino Night Zone.
- Badnik power: In both Knuckles' Chaotix and Sonic Advance 3, Eggman's robots would sometimes disgorge a ring instead of an animal captive when destroyed. In the former case, the rings were "depleted"; grey instead of gold, and not collectible. In Tails Adventures, Battle Kukku troops would sometimes drop rings when defeated.
- Move assists: Some of Sonic's upgraded moves, like the Light speed dash, see him fly along a chain of rings to get a speed boost or access otherwise unreachable areas.
- Move costs: Collected rings can be used to pay for using special moves during gameplay, like Eggman's rocket attack in Sonic R, or the racer's signature moves in Sonic Drift 2. In Sonic Unleashed, collecting rings fills up the Ring Energy gauge as well as the ring count itself; Ring Energy powers the Sonic Boost move. Sonic Heroes also uses rings to fill up a gauge, in this case the Team Blast gauge.
- Special Stage access: In Sonic 1, Sonic CD, and more recently Sonic 4, Sonic needs to have 50 rings or more upon reaching the goal signpost for a Giant Ring to appear as an entrance to the Special Stage. In Sonic the Hedgehog 2 (16-bit), a similar number opened up Star Circles above Star posts to provide access.
- Bonded rings: On top of its odd "depleted" rings, Knuckles' Chaotix also featured as a central gameplay element a pair of very unusual rings held by the player character and partner, which were bound together with some kind of magical elastic. In Tails Skypatrol, the flying fox has a similar ring which he uses to throw at enemies.
- Dummy rings: Tails and Rouge use fake rings as an anti-badnik explosive in Sonic Heroes. In Sonic 06, Tails uses a monitor full of fake rings.
- Ring Gates: Rings can also be used to unlock certain barriers which need rings to open.
Rings seem to have a higher purpose in the Archie comics. In one issue Sonic is able to use a ring to teleport himself, in another he uses one as a sort of fortune teller.
In the Sonic the Hedgehog cartoon Satam and anime Sonic X, Sonic used rings to give him a power boost.
- In Sonic and the Black Knight, rings seem to be hoarded by the Grand Kingdom's fairies, as it is golden, glowing fairy clouds that Sonic collects in-game. Nonetheless the HUD counter shows a picture of a ring, and rings explode out of the hedgehog when he takes a hit. Rings can, however, be seen in their normal form during the Legacy missions.
- Rings almost never appear in isolation, instead being found in clusters, like the standard 3-ring horizontal line in Sonic 1, or in circular arrangements in Sonic '06.
- In the opening of Sonic Colors, right before Sonic turns into the rocket, you can see some rings around him as a cube. Apparently, this is the only time rings have appeared in a CG cutscene.
- In the games for the Genesis, 32X and Sega CD, the ring collection sound effect alternates between the left and right speaker every time a ring is collected.