This article is about the unlockables in SRB2 itself. For a guide on custom unlockables, see Custom unlockables and emblems.
SRB2 features various unlockables that can only be accessed when the player completes a certain goal. Among them are bonus levels, new game modes, tools that aid with emblem collection, and various other features. Most unlockables are accessible from the "Secrets" menu on the title screen, which also contains a checklist of unlockables and their requirements. Not all unlockables are included on the checklist, however. The secrets menu only becomes accessible once the first unlockable has been unlocked, which is typically after completing the Single Player campaign for the first time. Custom unlockables can be created for modifications with the use of SOCs.
This article or section contains a spoiler, an unlockable, or a secret. Please leave the page if you do not wish to view spoilers.
SRB1 Remake: A remake of Sonic Robo Blast, the precursor to SRB2, using SRB2's own 2D mode. Playing through all levels in the remake unlocks a level select for it.
Mario Koopa Blast: An unlockable based on the Super Mario Bros. series, using SRB2's own Mario mode. Currently features only one level, Pipe Towers Zone.
Spring Hill Zone: A level based on the SEGA game NiGHTS Into Dreams, using SRB2's own NiGHTS gametype. Unlike the Special Stages, this map can also be explored in 3D mode.
Black Hole Zone: An exceptionally difficult eighth Special Stage. While it contains no additional emerald, an extra emblem is awarded for beating it.
Pandora's Box
This is a cheat menu that, when unlocked, is accessible from the in-game pause menu in Single Player. Several, but not all of these cheats can also be performed via console commands in development mode, but once Pandora's Box is unlocked, development mode no longer needs to be enabled to use them. The game will stop recording statistics once a cheat has been used. The following cheats are available:
Rings/Lives/Continues: Sets the amount of the player's rings, lives and continues.
Gravity: This changes the global gravity in the map. 0.5 is the default value. Higher values will make gravity stronger, thus decreasing the player's jump height. Lower values will make gravity lighter. Negative values reverse gravity but do not flip the player, so jumping will cause players to stick to the ceiling in their jumping animation.
Throw Rings: When enabled, the player is able to throw collected rings like in Match mode. The rings can hurt enemies as well as bosses.
Get All Emeralds: This option instantly gives the player the seven Chaos Emeralds.
Destroy All Robots: This option destroys all of the enemies and bosses inside the current map. Points will be awarded as if the player had destroyed all of them separately, rather than in one move.
Ultimate Cheat: This is a prank dating back to SRB1 that simply closes the game upon selecting it. Because the name suggests a powerful cheat, an in-joke developed around it where community members would tell new players that the ultimate cheat only works when bizarre or impossible requirements are met.
Other unlockables
Record Attack: This mode allows the player to replay the Single Player maps and attempt to establish records for fastest time, highest score and most collected rings. Each map becomes available in Record Attack once it has been visited in the regular game.
NiGHTS Mode: Similarly to Record Attack, this mode allows the player to replay the game's NiGHTS maps (Special Stages and Spring Hill Zone) and attempt to achieve an A rank or establish records for fastest time and highest score. Each map becomes available in NiGHTS Mode once it has been visited/unlocked.
Play Credits: This feature replays the game's credits. During the credits, you can press the jump or spin button to return to the title screen.
Sound Test: This feature lets you toggle through the sound effects available in SRB2 and play them. It is based on a similar feature in the classic Sonic games. The console variable soundtest can also be used to access this feature – this does not require the unlockable listed in the Secrets menu to be accessible, however.
Emblem Hints: These are hints in haiku form that give the player vague information about the location of the in-map emblems in the Single Player stages.
Emblem Radar: When enabled, a radar will appear on the HUD for each emblem on the map that has yet to be collected. If the player is close to an emblem, the corresponding radar will become colored and a beep sound will play periodically. The color of the radar and the frequency of the beep sound will change as the player gets closer to the emblem. The feature can be turned on and off in the emblem hints menu, or through the console variable itemfinder.
Level Select: Unlike the character-specific level selects that completed save slots turn into, this level select allows the player to choose any character. However, no status information is saved, so the player always starts out with three lives, one continue and no emeralds.