Difference between revisions of "Ashura"

Revision as of 02:26, 12 December 2009

A fan rendering of Ashura.

Ashura is the fan-atoned name of the glitched-palette phenomena found in Sonic the Hedgehog 2's Emerald Hill Zone.

Getting Ashura

In order to reproduce the Ashura glitch, the zone select and debug codes must be active. Upon activation, proceed to one of the two acts of Emerald Hill Zone, as it does not occur in any other level. When the zone begins, press . Sonic will be a ring, signifying that debug mode is active. Press four times; Sonic should be four rings in a row going up or down. Then, hold and for about 5 seconds, then go back to the beginning of the level and keep pressing until Sonic appears as the top of a waterfall. Sonic or an item may not be visible, but Sonic is still there. Continue to hold and for about five seconds, then press . If performed correctly Sonic should appear with a green and black palette.

Explanation

The reason for the Ashura palette glitch is a result of several objects being loaded into the Sprite Status Table at a given point in time. Since RAM on the Mega Drive is in limited quantity, only so many objects can be loaded into the status table before it reaches its alloted limit. When a mass of waterfall objects are placed using debug mode, this overloads the SST to a point that exceeds the SST's reserved RAM area; since the palette cache used by the game to update CRAM is located after the SST in system memory, SST data becomes parsed as color data in the reserved palette cache area and is loaded into CRAM accordingly. Because of this, the green color is purely a coincidence--it is not intentional.

Similar palette errors can occur upon porting the Sonic 1 sound driver to Sonic 2; if Sonic loses rings whilst underwater, it will overload the SST and spill into the palette cache, corrupting the underwater character palette line.

Miscellaneous

Though only a palette glitch, Ashura is one of the four characters possible in Yuski the Dog's SMS ROM hack, Sonic vs. Os Mauniks. Ashura was even hacked into Sonic R [1] and Sonic Heroes [2]. Also, there is a way to get an "Ashura"-esque Chao in Sonic Adventure 2: Battle; it is the dark/run Shadow the Hedgehog Chao. Additionally, Ashura is the titular co-villain in the fan-made game Ashura Dark Reign.

External Links

Video of Sonic 2 glitch

@@ Line 1: / Line 1: @@
 [[Image:Ashura1.jpg|thumb|right|A fan rendering of Ashura.]]
-Also known as "The Green Demon," '''Ashura''' is the name of the glitched-palette character found in ''[[Sonic the Hedgehog 2 (16-bit)|Sonic the Hedgehog 2]]''<nowiki>'</nowiki>s [[Emerald Hill Zone]].
+'''Ashura''' is the fan-atoned name of the glitched-palette phenomena found in ''[[Sonic the Hedgehog 2 (16-bit)|Sonic the Hedgehog 2]]''<nowiki>'</nowiki>s [[Emerald Hill Zone]].
 == Getting Ashura ==
-To get Ashura, the [[Cheat_Codes:Sonic_the_Hedgehog_2_(16-bit)#Cheat_Codes|zone select and debug codes]] must be active. Then, go to one of the two EHZ acts because the glitch only happens in Emerald Hill Zone. When the zone begins, press {{b}}. [[Sonic]] will be a [[ring]], signifying that [[debug mode]] is active. Then, press {{A}} four times. Sonic will be four rings in a row going up or down. Then, hold {{C}} and {{right}} for about 5 seconds, then go back to the beginning and keep pressing {{a}} until Sonic is the top of a waterfall. Sonic or an item may not be visible, but Sonic is still there. Again, hold {{C}} and {{right}} for about five seconds. Then press {{B}} and Sonic will be Ashura, or, green Sonic.
+In order to reproduce the Ashura glitch, the [[Cheat_Codes:Sonic_the_Hedgehog_2_(16-bit)#Cheat_Codes|zone select and debug codes]] must be active. Upon activation, proceed to one of the two acts of Emerald Hill Zone, as it does not occur in any other level. When the zone begins, press {{b}}. [[Sonic]] will be a [[ring]], signifying that [[debug mode]] is active. Press {{A}} four times; Sonic should be four rings in a row going up or down. Then, hold {{C}} and {{right}} for about 5 seconds, then go back to the beginning of the level and keep pressing {{a}} until Sonic appears as the top of a waterfall. Sonic or an item may not be visible, but Sonic is still there. Continue to hold {{C}} and {{right}} for about five seconds, then press {{B}}. If performed correctly Sonic should appear with a green and black palette.
-== Dispelling Ashura Myths ==
+==Explanation==
-While there is no known reason why the glitch was named Ashura, the leading theory says that it has something to do with a Hindu god who also shares the black stripe and green body. Ashura is '''not''' a secret character or anything special in ''Sonic 2'', however.  It is merely a glitch.
+The reason for the Ashura palette glitch is a result of several objects being loaded into the [[Sprite Status Table]] at a given point in time. Since RAM on the [[Mega Drive]] is in limited quantity, only so many objects can be loaded into the status table before it reaches its alloted limit. When a mass of waterfall objects are placed using debug mode, this overloads the SST to a point that exceeds the SST's reserved RAM area; since the palette cache used by the game to update CRAM is located ''after'' the SST in system memory, SST data becomes parsed as color data in the reserved palette cache area and is loaded into CRAM accordingly. Because of this, the green color is purely a coincidence--it is not intentional.
+Similar palette errors can occur upon porting the ''[[Sonic 1]]'' sound driver to ''Sonic 2''; if Sonic loses rings whilst underwater, it will overload the SST and spill into the palette cache, corrupting the underwater character palette line.
 == Miscellaneous ==