Demo 4

Demo 4 is an outdated version of SRB2, released on December 25th, 2001. It introduced several new elements of the game, most notably unlockable and secret content, among them Special Stages, Castle Eggman Zone and date-activated secrets. Capture the Flag mode was also introduced in this demo.

Demo 4.1 was a minor release released on January 6th, 2002, that fixed a few serious bugs in Demo 4. It also introduced the placeholder Knuckles sprites, modeled in 3D by community member DOHlberg (now known as JackelZXA) and then captured into sprite form for use in SRB2. The original model used to make the placeholder sprites has since been lost. Contrary to some popular theories, this version of Knuckles was not based on a plush toy.

Demo 4.32 to Demo 4.35 were updates of Demo 4 to Doom Legacy v1.32; for these versions, see Demo 4.35.

New features

Special Stages

A screenshot of the first Special Stage from Demo 4.

Special Stages, and therefore a proper way of collecting Chaos Emeralds, were introduced in Demo 4. Previously, the emeralds themselves had been hidden in the Single Player levels. They were replaced with Special Stage Tokens that send the player to a Special Stage upon finishing the level. The Chaos Emeralds themselves were given new sprites.

The original Special Stages were small arenas in which the player had to collect a certain amount of rings in a certain time. Some of the Special Stages featured water as a hazard; if the player was submerged in water, the timer counted down faster than normal. While the maps themselves would be changed in subsequent versions, the general format stayed in place until the Special Stages were replaced with NiGHTS maps in v2.1. The Special Stages in Demo 4 were created by Sonikku and were much more difficult than the ones in later versions due to very restrictive time limits. The last special stage was a copy of the first, presumably because a seventh one had not yet been designed.

Each Special Stage had its own music in this release: The first two Special Stages used original music, while the rest of the Special Stages (as well as Christmas Hunt Zone) used MIDIs of music from the anime TV series Ojamajo Doremi. In v1.01, a new Special Stage theme would replace all of these and would continue to be used in future releases until v2.1. However, the music for Demo 4's first Special Stage was later re-added in v1.09.4 as a bonus track.

None of the Special Stages in this demo used title cards, and therefore they have no names. However, later Special Stages in this format continued not to use title cards, even after level headers were introduced, until the release of v2.1.

Castle Eggman Zone

A new three-act zone, Castle Eggman Zone, was added as an unlockable. This was the original version of Castle Eggman Zone seen in the Single Player level line-up for the Final Demo versions. The whole zone would later be remade in v2.0. Because a secrets menu did not yet exist, the player would be warped to it after finishing Techno Hill Zone Act 1 with all seven emeralds. At this point, the Single Player campaign looped by warping back to Greenflower Zone Act 1 after the player has cleared THZ1, which made it possible to collect all seven emeralds even though there were only four tokens by playing through the game twice. However, attempting to cheat by warping to any of these maps would result in the game crashing, displaying an error message telling you not to do so. The introduction of the Chaos Emeralds and a "certain unlockable" for them was heavily hyped in the period before Demo 4's release. The developers would jokingly tease the community by calling the unlockable "Cas**HACK**".

At this point, Castle Eggman Zone Act 1 largely used GFZ's texture set, with the exception of the castle at the end. Acts 2 and 3, however, are basically identical to their Final Demo versions. RedXVI also appeared as an easter egg in act 2 (see article for more information).

Date-activated secrets

Demo 4 was the first release to feature date-activated secrets. The secrets were activated by playing the game on a specific holiday, setting the computer's clock to the date of that holiday or loading the game with the associated command line parameter. Date-activated secrets were featured in all subsequent SRB2 releases until they were removed in v2.0. Demo 4 featured two date-activated secrets: Christmas mode and Mario mode. The resources for both of these were hidden in WAD files disguised as DLL files.

Christmas

Christmas mode was activated during the Christmas season (from December 24th to January 5th) or with the -xmas parameter. The resources for this were stored in 3drend.dll. When activated, several of the game's graphics, including many of the textures used by the Single Player levels, would be replaced with Christmas-themed graphics. The music was also replaced by Christmas tunes. It also snowed in all levels; snowflakes fell from any sector with a sky ceiling nearby the player.

Exclusively for Demo 4, clearing Techno Hill Zone Act 1 in Christmas mode takes the player to Christmas Hunt Zone, a level showcasing the new Emerald Hunt level type for Single Player, following a cutscene where Santa asks Sonic to help him find his stolen clothes. The gameplay in Emerald Hunt levels is similar to that of Knuckles' levels from Sonic Adventure and Sonic Adventure 2, where the player hunted for three Chaos Emeralds in the map with the help on an on-screen radar, after which the level automatically ended. However, in Christmas mode (including Christmas Hunt Zone), these were replaced with three pieces of Santa's clothes, and Christmas Hunt Zone required the player to take the clothes to Santa after collecting all three items of clothing in order to finish the level. Also during Christmas in Demo 4, the inner portion of Christmas Hunt Zone took the place of MAP06 as a Match stage.

After clearing Christmas Hunt Zone, another cutscene would play in which Santa awards Sonic the ability to use the Snow Buster, allowing the player to fire snowballs at enemies in any level using the Ring Throw button (each snowball costing a ring to use). If the Ring Throw button was held down for at least two seconds and then released, a bigger snowball is fired that is not destroyed on collision with enemies or walls, allowing multiple enemies to be killed in one shot. However, each big snowball costs five rings to use, and they disappear automatically after ten seconds. The Snow Buster ability only lasted for the current game session, but could be kept if the session was saved and later reloaded.

In v1.01, Christmas Hunt Zone became an unlockable level separate from Christmas mode. However, Christmas Hunt Zone's cutscenes, the Snow Buster ability and Santa Claus were removed. Christmas Hunt Zone's differences from the normal Emerald Hunt gameplay were also removed: The player now hunted for Chaos Emeralds instead of Santa's clothes, and the level automatically ended after collecting all three emeralds. Christmas Hunt Zone, along with Christmas mode, was later removed from the game in v2.0. The replacement for MAP06 was also readded in v1.01, received further modifications, and was given the name "Christmas Match Zone". However, it was dropped from the Match rotation afterwards in v1.08, and was never used again.

Mario

Mario mode was activated on New Year's Day (January 1st only) or with the -mario parameter. The resources for this were stored in menuitem.dll. When activated, the title screen received a Mario sky background, several sounds were changed to Mario-related sounds, all Crawlas were replaced with Goombas and all rings were replaced with coins. GFZ1's music and the level clear jingle were replaced with music from the Mario games. Additionally, GFZ1 was replaced by Mario Goomba Blast Zone Act 1, a level themed after World 1-1 from Super Mario Bros., which later became the first act of the Mario Koopa Blast unlockable in v1.01 (it was eventually replaced by Pipe Towers Zone in v2.1).

At this point, the behavior for the ? blocks in Mario Goomba Blast Zone Act 1 had not yet been implemented; for the time being, the items the blocks were supposed to give the player were instead placed on top of the blocks in the level.

Capture the Flag

Demo 4 introduced Capture the Flag mode, a multiplayer gametype similar to Match but played with two opposing teams who each control a base with a flag and try to steal the other team's flag. The gameplay mechanics were mostly the same as they are today, except that flags did not return to the base automatically upon being reclaimed. Instead, players had to bring them back themselves. Two levels were added for Capture the Flag mode. Additionally, Demo 4 included a roster of seven Match levels, of which only Zero Ring Zone returned from Demo 3.

Characters

Sonic and Tails' sprites were now fully complete (for the time being), replacing the remaining Sonic Xtreme placeholder sprites used by them. New falling down and grabbing air bubble animations were introduced for both characters.

Knuckles received his climbing ability. Moving sideways while climbing was not yet possible with the turning keys, only the strafing keys. The gliding animation was used while climbing.

Super Sonic's appearance was changed. Instead of using the placeholder sprite from SRB2 Christmas, Super Sonic now appeared as regular Sonic with an added Superman cape, as a new placeholder and a joke on the name "Super Sonic". Later versions of SRB2 would add to this "Superman" Sonic joke by adding Superman's logo as Super Sonic's life icon, and adding the theme tune from Superman: The Animated Series as his music. His ability to run on water was removed, although it would later return in v1.09.

Other changes

Several new enemies were coded into the game by this version: the Jetty-Syn Bomber and Gunner, the Deton, and the Crawla Commander. The Jetty-Syns were featured as enemies in Techno Hill Zone Act 1 and Castle Eggman Zone, though they also appeared in Greenflower Zone Act 2 if the "Hard" skill level or higher was chosen. The Deton appeared in Castle Eggman Zone Act 1 in a hidden room, as well as Techno Hill Zone Act 2 (see below). The Crawla Commander, however, did not yet have any sprites at this stage; they would not be added to the game until SRB2 2k3.
The Armageddon Shield's blast was now activated by pressing the spin button after jumping, rather than the jump button. This allowed players to use their special abilities without activating the blast.
Rings could now be made to float using Ambush flag, which raised them 32 units above the ground automatically on map load. Previously, all floating rings had to be raised using floors that instantly lowered on map load. The rings in all three acts of Greenflower Zone were adjusted to use this flag instead of instantly-lowered floors; an exception to this was the circle of rings high in the air near the start of GFZ1, as it was not yet possible to give map Things a Z offset at this point. However, Techno Hill Zone 1 continued to use instantly-lowered floors to raise all rings in the level above the ground until v1.04.
The vine-covered version of the GFZROCK texture was now applied to the first cave in GFZ2.
The extra life awarded for collecting 50,000 points was now awarded immediately rather than at the start of the next level.

Levels

Single Player levels

Match stages

Note that the level names did not exist at the time, as Demo 4 did not yet have title cards for the multiplayer levels and the Special Stages.

MAP06 (Demo 4) (Unnamed, never used again)
MAP07: Grass Plateau Zone
MAP08: Airborne Temple Zone
MAP09: Starlit Warehouse Zone
MAP10: Orange Crater Zone
MAP11: Air Haven Zone
MAP12: Zero Ring Zone

Capture the Flag stages