'Sonic the Hedgehog 2 "Beta 4" is a prototype version of Sonic the Hedgehog 2 (16-bit). It is one of many internal prototypes released by drx during the February 23rd, 2008 proto release.
Beta 4 and the subsequent "beta 5", "beta 6", "beta 7" and "beta 8" are internal builds of the game, never intended to be seen by the general public in any form. Only days separate the build dates of these prototypes, and all were created towards the end of the game's development cycle, with significantly fewer differences from the earlier prototypes available online. Beta 4 has a time stamp of 1992-09-18 16:26, meaning it was created just over two months before the final game's release.
The "beta 4" name originates from Sega themselves, having presumably succeeded a "beta 1", "2" and "3" in the days and weeks prior to beta 4's release. Confusingly this numbering scheme is not thought to include the older "Nick Arcade" and "Simon Wai" prototypes, which were produced many months before beta 4 (that is to say, these are not "beta 1" and "beta 2", respectively). Sega likely only used the term "beta" in the final few weeks of the game's development, though outside of the company, the word is often used to describe prototypes at a range of development stages.
- Level select is activated with + , no code is required.
- Debug is activated by holding when selecting a level on the level select screen. It can also be activated by holding when you die, no code is required.
- Some of the zones that play after the Title Screen are still using the demos from the Nick Arcade/Simon Wai builds.
- The title cards are implemented.
- This build also features a severely limited debug mode. Item placement mode is not accessible, nor is Sonic invulnerable. The coordinate display functions are working, however. Item placement mode can be forced using patch codes, but debug remains limited as the player cannot move in item placement mode and items can be placed once.
- The Spike damage behavior works the same way as it does in Sonic 1.
- When Sonic dies, the camera follows him all the way to the bottom of the level.
- Even with debug or level select off, you can still restart the game by pressing when the game is paused.
- Invincibility stars are different.
- Screen doesn't move up/down when you hold the or arrows.
- The Special Stages are different in color and design from the Final Version. The "(x) rings to go!" message never activates, and is not active until Beta 7.
- Emerald Hill Zone is listed as "Green Hill Zone" in the level select screen.
- The slots in Casino Night Zone do not work.
- There's a different sound in Casino Night Zone when you go into the slots.
- Boss music does not change in Wing Fortress Zone or Death Egg Zone.
- The first cutscene in Wing Fortress Zone doesn't have any sound effects.
- The spiky platforms in the boss of Wing Fortress Zone gets destroyed if the laser touches them.
- The Death Egg only takes 8 hits.
- Metal Sonic comes down slower.
- You can control Sonic after beating the Death Egg.
- Wood Zone and Genocide City Zone have been removed from the level select screen.
- Hidden Palace Zone is disabled in the level select.
- Through hacking, Hidden Palace Zone can be accessed and it is a garbled mess just like in the final, but Badniks and object art are still intact. Though it uses its original object layout, it uses Hill Top Zone Act 2's level layout for some reason.
- When passing Death Egg Zone, no ending is shown. Instead, the game resets with no credits.
2 Player Mode
- 2P special stage, towards the end rings glow and side-stripes glow. This is the result of the end goal being loaded.
- 2P special stage. Cannot jump over other player. However, hitting a mine puts you in front.
- The text for 2 Player VS Mode's Special Stage after winning 1 round (Most Rings Wins!) is now Win Twice Win All! instead.
- The Eggman monitor doesn't work.
- Tails' icon is always listed as "Miles"
- There are no invincibility stars
- There is no one minute countdown displayed on the other player's screen if the opposite player finishes.
- In the fourth Special Stage, there are only 42 rings in the first section, yet 45 rings are required. Therefore, it is impossible to get the fourth Chaos Emerald, and consequently impossible to get Super Sonic without hacking.
- When Tails drowns, Sonic will also drown.
- The collision detection in Emerald Hill Zone and Aquatic Ruin Zone is a bit wonky.
- One of the elevators in Casino Night Zone doesn't work properly.
- You can get stuck if you Spin Dash into a rock in Hill Top Zone.
- Oil Ocean Zone has some background and collision detection issues.
- Metropolis Zone Act 3 cannot be played without using Level Select. Completing Metropolis Zone Act 2 takes you to Sky Chase Zone.
- The propellers from the Wing Fortress will hurt you in Sky Chase Zone.
- You can run past Eggman in Death Egg Zone.
Sonic Retro discussion thread