- For the pick-up emerald objects, see Thing types > Other collectibles.
The seven Chaos Emeralds
The Chaos Emeralds are hidden items in most Sonic games, and collecting all seven is necessary to get the true ending. In SRB2, the seven Chaos Emeralds are used to allow Sonic to transform into Super Sonic (or the equivalent Super form for other characters, outside of Single Player/Coop), as well as unlock secrets. Sonic can only transform, however, if the player has at least 50 rings, and is not holding a shield.
The exact implementation of the Chaos Emeralds, as well as the method to collect them, differs depending on the gametype being played, as does the behavior of Super forms.
To collect the emeralds, the player must collect an Emerald Token in one of the stages. When the stage is completed, the player is warped to one of seven Special Stages. In these stages, the player is transformed into Super Sonic (regardless of character) and must fly around the track to collect enough blue spheres to destroy the Ideya Capture, and return to the start again within the time limit for the Special Stage. If this is done successfully, the player is rewarded with a Chaos Emerald. If not, the Special Stage ends, and the player earns nothing. If more than one Emerald Token is collected in a stage, a player re-enters either the same Special Stage, or enters a new one, depending on how the previous Special Stage went.
In Cooperative mode, emerald-collecting is much the same as in Single Player, except with multiple players – the emeralds are shared by all players in the game, but only those players who are playing as Sonic can turn Super in regular, unmodified SRB2.
Match/Capture the Flag
In the Match and Capture the Flag gametypes (not including Team Match), the Chaos Emeralds are collectable within the stages themselves, and can allow one of the players in the game to turn Super regardless of character. Because of this, the emeralds are considered an important part of these gametypes, as they can potentially decide the winning players or team. The console variable
powerstones can be used to turn this feature on or off; by default it is turned on.
Each Match/CTF stage contains a large amount of Match Chaos Emerald Spawns in which the seven Chaos Emeralds can randomly appear. At the start of the Match/CTF session, each of the emeralds will spawn at the location of one of these after a random time between 1 and 2 minutes. Once spawned, they can each be collected by one of the players – unlike in Single Player/Coop these emeralds are not shared by all players, but are stored as separate collections for individual players. The displayed player's own collection is visible on the Game HUD. The emerald collections of all players in the game session can be viewed through the Rankings/Scores HUD, which displays the icons for the emeralds collected by each player besides their own life icons in the player listings.
Being damaged by an opponent or a hazard will cause a player to spill all their collected emeralds if they lack a shield. However, emeralds can also be tossed by players, allowing other players to obtain the emeralds – this tactic can be useful in CTF in particular. If a spilled/tossed emerald is not collected within 12 seconds, or it falls into a death pit, it will disappear from the map. Any missing emeralds will eventually be respawned at a Chaos Emerald spawn again up to approximately a minute afterwards.
If a player manages to collect all seven Chaos Emeralds as well as 50 rings and then double-jumps provided they don't have a shield, they will turn into their character's Super form. This gives them a variety of potential bonuses as well as immunity to some hazards, the ability to hurt opponents by ramming them, and increased speed. However, if they are hit by an opponent's ring, or a hazard they are not immune to, they will lose ten rings that do not spill on the ground. For every five minutes a character is Super, this doubles. There is no blinking timer after this, so multiple hits can be scored on a super character in a brief period of time, and the Scatter Ring can hit multiple times at once from the same shot. When the player's ring count drops to zero, the player's Super form will wear off and the player returns to normal, while the Chaos Emeralds will respawn again from the Chaos Emerald spawns up to approximately a minute afterwards.
Given the two different systems of collecting Chaos Emeralds in-game detailed above, the internal storage methods for Chaos Emeralds also differ accordingly:
- In Single Player/Coop, the Chaos Emeralds collected by all players are stored in the global variable
emeralds, which can be accessed (but not modified directly) with the use of Lua scripts.
- In Match/Capture the Flag, the Chaos Emeralds collected by each player are stored using the player power
pw_emeralds. In Lua, this power can be accessed or modified for a particular player with the code
To store the collected emeralds in both of the above systems, the Chaos Emeralds themselves are represented by a series of toggles known as the Chaos Emerald flags. These are listed below:
||Light Blue Emerald|
The Lua function
All7Emeralds can be used to determine whether a given variable contains all of the above Chaos Emerald flags within.
There are several sets of emerald sprites used by the game. Among them are
EMMYH0 (used by the emerald token),
CEMGH0 (used by the emerald Objects),
CHAOS7 (full-size sprites used by the HUD), and
TEMER7 (miniature sprites used by the Match/CTF HUD).