Sonic the Hedgehog CD (Aug 1, 1993 prototype)

A late prototype of Sonic the Hedgehog CD for the Sega CD.
==Notes==
* Another copy of this prototype was found on another CD-R. The new copy is a perfect match for the previous dump. A scan of the new CD can be found below.
* Level select can be activated at the title screen by pressing B
* Minor code changes in all files.
* Wacky Workbench Act 2 (Past and Good Future) and Stardust Speedway Act 2 (Present and Good Future) contain the most differences in this build (R62B, R62C, R72A, R72C).
=== Palmtree Panic Zone Act 2 (R12A/B/C/D__.MMD) ===
A critter that jumps around in good future is removed in the final:
 054E 028E A401 E000
ppz2c_animal_801.png | 801
ppz2c_animal_final.png | Final
A spring and a rock that stop you were added in the final. The goal post is also moved to the right in the final.
 26C8 02D2 9600 E000 (goal post)
is replaced by
 2628 42D8 0A0A 2000 (spring - past)
 2630 42D0 0A0A C000 (spring - present, future)
 2730 02C4 9600 C000 (goal post - present, future)
 2738 02CB 9600 2000 (goal post - past)
 27A0 02E0 1B00 E000 (rock)
ppz2a_goal_801.png | 801
ppz2a_goal_final.png | Final
ppz2a_goal2_801.png | 801
ppz2a_goal2_final.png | Final
=== Metallic Madness Zone Act 2 (R82B__.MMD, R82C__.MMD) ===
The prototype has two places where Mini Sonic can fall through the wall in Metallic Madness Act 2. The final adds the following two objects which act as barriers to fix this bug:
 0910 0710 0900 2000
 1A20 0110 0900 E000
Sonic CD 810 - MMZ2 Past Mini Sonic Collision.gif | Past (0910 0710)
Sonic CD 810 - MMZ2 Good Future Mini Sonic Collision.gif | Good Future (1A20 0110)
The block causing the first bug was also reinforced with collision on the top and bottom so that even if you fall into it, you won't fall through the bottom any more. The column causing the second bug was also reinforced making it entirely solid. In the prototype, it has collision holes in the top corners and it's hollow inside. 
 
=== Quartz Quadrant Zone Act 3 (R53C__.MMD, R53D__.MMD) ===
The boss in both good and bad future has a different color
==== Good Future ==== 
qqz3c_boss_510.png | 510
qqz3c_boss_712.png | 712
qqz3c_boss_801.png | 801
qqz3c_boss_final.png | Final
==== Bad future ====
qqz3d_boss_510.png | 510
qqz3d_boss_712.png | 712
qqz3d_boss_801.png | 801
qqz3d_boss_final.png | Final
The background in Bad Future starts higher than in the final.
qqz3d_start_510.png | 510
qqz3d_start_712.png | 712
qqz3d_start_801.png | 801
qqz3d_start_final.png | Final
qqz3d_bg_510.png | 510
qqz3d_bg_712.png | 712
qqz3d_bg_801.png | 801
qqz3d_bg_final.png | Final
=== Visual mode (VM____.MMD) ===
In builds 712 and 801, there are 5 patterns that are loaded into the same place in Video RAM in succession (overwriting each other). The last pattern (#5) is changed between 712 and 801, fixing the OPENNING typo. Patterns #1-#4, which presumably show the development progression of the Visual Mode are removed in the final, leaving only pattern #5.
Pattern	712	801	Final	Image
#1 	✓ 	✓ 	 	
#2 	✓ 	✓ 	 	
#3 	✓ 	✓ 	 	
#4 	✓ 	✓ 	 	
#5 	✓ 	 	 	
#5 	 	✓ 	✓ 	
==== OPENNING typo ====
Sonic_CD_VM_712.png | 712
Sonic_CD_VM_final.png | 801 / Final
==Screenshots==
sonic cd 8-1-93 title.png|Title screen
sonic cd 8-1-93 (1).png|Stardust Speedway Zone Act 3 (Good Future)
sonic cd 8-1-93 (2).png|Palmtree Panic Zone Act 1 (Present)
sonic cd 8-1-93 (3).png|Wacky Workbench Zone Act 2 (Past)
sonic cd 8-1-93 (4).png|Wacky Workbench Zone Act 2 (Good Future)
sonic cd 8-1-93 (5).png|Stardust Speedway Zone Act 2 (Present)
==Videos==
<youtube width="320" height="240">AoDQv-rlCl8</youtube>
==Files==
==Header==
00000100 53 45 47 41 20 4d 45 47 41 20 44 52 49 56 45 20 SEGA MEGA DRIVE 
00000110 28 43 29 53 45 47 41 20 31 39 39 33 2e 41 55 47 (C)SEGA 1993.AUG
00000120 53 4f 4e 49 43 20 54 48 45 20 48 45 44 47 45 48 SONIC THE HEDGEH
00000130 4f 47 2d 43 44 20 20 20 20 20 20 20 20 20 20 20 OG-CD 
00000140 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 
00000150 53 4f 4e 49 43 20 54 48 45 20 48 45 44 47 45 48 SONIC THE HEDGEH
00000160 4f 47 2d 43 44 20 20 20 20 20 20 20 20 20 20 20 OG-CD 
00000170 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 
00000180 47 4d 20 47 2d 36 30 32 31 2d 31 30 20 31 30 35 GM G-6021-10 105
00000190 4a 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 J 
000001a0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 
000001b0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 
000001c0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 
000001d0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 
000001e0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 
000001f0 4a 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 J 
==Origin==
Sonic the Hedgehog CD (Aug 1, 1993 prototype) - disc.jpg|Disc front
Sonic CD 1.05 Back - Second copy.png|Disc back (second copy)
Sonic CD 1.05 Fron - Second copy.png|Disc front (second copy)