G-Mode Technical Details - Revision history

Aquanight at 15:56, 20 December 2025

2025-12-20T15:56:30Z

Aquanight: Table of x-ray state comparison

2025-10-12T03:56:37Z

Table of x-ray state comparison

Aquanight: Technical info about the MB Light Pillar technique

2025-04-05T19:44:49Z

Technical info about the MB Light Pillar technique

Maddo: Explain how power bomb explosion status mutes the sound

2025-03-31T15:43:20Z

Explain how power bomb explosion status mutes the sound

Aquanight: Some clarifications on how the x-ray input routine relates to normal conditions.

2025-03-29T04:14:35Z

Some clarifications on how the x-ray input routine relates to normal conditions.

Aquanight at 20:23, 28 March 2025

2025-03-28T20:23:13Z

Aquanight: Documentation of X-Ray Input Handler and relevance to G-Mode Mobile/Immobile/Morph

2025-03-28T20:22:00Z

Documentation of X-Ray Input Handler and relevance to G-Mode Mobile/Immobile/Morph

Maddo: Clarify boss room exceptions

2025-03-19T02:12:57Z

Clarify boss room exceptions

Maddo: Correction on fireflea rooms

2025-03-19T01:55:44Z

Correction on fireflea rooms

Maddo: Add detail on how FX HDMA objects affect Crystal Flash behavior

2025-03-19T01:46:20Z

Add detail on how FX HDMA objects affect Crystal Flash behavior

← Older revision		Revision as of 15:56, 20 December 2025
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	Because Light Pillar delays the R-Mode Forced Stand, it does not benefit from "clipping" the bottom of Samus's energy tank twice, as the normal suitless R-Mode tactic does. Thus, a no-Varia attempt would reduce only 1 point of energy lost instead of 2. Thus it does not allow Samus to survive Rainbow Beam with one fewer tank, but it would allow some combinations that would not work with normal R-Mode. For example, while standard game does not have more than 4 reserve tanks, a 1+5 option is possible which may be of relevance in hacks/randomizers.		Because Light Pillar delays the R-Mode Forced Stand, it does not benefit from "clipping" the bottom of Samus's energy tank twice, as the normal suitless R-Mode tactic does. Thus, a no-Varia attempt would reduce only 1 point of energy lost instead of 2. Thus it does not allow Samus to survive Rainbow Beam with one fewer tank, but it would allow some combinations that would not work with normal R-Mode. For example, while standard game does not have more than 4 reserve tanks, a 1+5 option is possible which may be of relevance in hacks/randomizers.
		+
		+	It is possible to create a similar effect in G-Mode: at the end of the auto-reserve activation used to enter G-Mode, it is possible to time a frame perfect input of either Item Select or Item Cancel, and continuing to hold Run. Instead of entering R-Mode, Samus will enter G-Mode but the X-Ray beam will remain active when time unfreezes. If Samus enters G-Mode Immobile, the X-Ray beam can be turned around as normal. Once Samus becomes mobile, the beam's left/right orientation will become fixed, but it can still be moved up and down. The beam will center from one tile above Samus's feet: for example its origin will appear to float above Morph Ball.
		+
		+	Run must be held to keep the X-Ray beam visible, which can complicate attempts to Crystal Flash. Like Light Pillar, Samus can safely use a reserve auto-trigger without ending G-Mode in this state.

	====FX-dependent HDMA objects====		====FX-dependent HDMA objects====

← Older revision		Revision as of 03:56, 12 October 2025
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	If the room FX uses 2 slots, then it will still be possible to lay a single Power Bomb (after a Crystal Flash), and it can give Samus a boost, but it will fail to explode, and it will still not be possible to use X-Ray afterward, nor to lay additional Power Bombs.		If the room FX uses 2 slots, then it will still be possible to lay a single Power Bomb (after a Crystal Flash), and it can give Samus a boost, but it will fail to explode, and it will still not be possible to use X-Ray afterward, nor to lay additional Power Bombs.
		+
		+	==Comparison of X-Ray States==
		+
		+	This table provides a side-by-side comparison of all X-Ray related conditions:
		+
		+	{\| class="wikitable"
		+	\|-
		+	! State !! Time Frozen !! Enemy Projectiles !! PLMs !! Animated Tiles !! Palette FX !! X-Ray HDMA Object Count !! Input Handler !! X-Ray State
		+	\|-
		+	\| Normal Gameplay \|\| No \|\| Enabled \|\| Enabled \|\| Enabled \|\| Enabled \|\| 0 \|\| Normal \|\| No object active
		+	\|-
		+	\| Normal X-Ray \|\| Yes \|\| Disabled \|\| Disabled \|\| Disabled \|\| Disabled \|\| 1 \|\| X-Ray \|\| 2 (active beam)
		+	\|-
		+	\| R-Mode \|\| No \|\| Enabled \|\| Enabled \|\| Enabled \|\| Enabled \|\| 1 \|\| Normal \|\| 5 (pending shutdown)
		+	\|-
		+	\| R-Mode X-Ray \|\| Yes \|\| Disabled \|\| Disabled \|\| Disabled \|\| Disabled \|\| 2 \|\| X-Ray \|\| 2 (active beam)
		+	\|-
		+	\| R-Mode Light Pillar \|\| No \|\| Enabled \|\| Enabled \|\| Enabled \|\| Enabled \|\| 1 \|\| Normal \|\| 2 (active beam)
		+	\|-
		+	\| G-Mode (Direct, Immobile) \|\| No \|\| Disabled \|\| Disabled \|\| Disabled \|\| Disabled \|\| 1 \|\| X-Ray \|\| 5 (pending shutdown)
		+	\|-
		+	\| G-Mode (Direct, Mobile) \|\| No \|\| Disabled \|\| Disabled \|\| Disabled \|\| Disabled \|\| 1 \|\| Normal \|\| 5 (pending shutdown)
		+	\|-
		+	\| G-Mode (Indirect) \|\| No \|\| Disabled \|\| Disabled \|\| Disabled \|\| Disabled \|\| 0 \|\| Normal \|\| No object active
		+	\|-
		+	\| X-Mode \|\| Yes \|\| Disabled \|\| Disabled \|\| Disabled \|\| Disabled \|\| 1 \|\| Normal \|\| 2 (active beam)
		+	\|}

← Older revision		Revision as of 19:44, 5 April 2025
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	The exception in Mother Brain Room is significant, as the Light Pillar technique would otherwise not be possible (see [[R-Mode#Light_Pillar_Mother_Brain]]).		The exception in Mother Brain Room is significant, as the Light Pillar technique would otherwise not be possible (see [[R-Mode#Light_Pillar_Mother_Brain]]).
		+
		+	====Light Pillar Details====
		+
		+	The Light Pillar technique used in the Mother Brain fight allows Samus to survive the Rainbow Beam attack with few or even no Energy Tanks, using Reserve Tanks instead. Normally, this cannot be done when reserves refill automatically, the refill will "waste" much of the reserve tank energy once Samus has reached maximum, while manual refilling is prevented due to not being able to pause the game while rainbow beam is in progress.
		+
		+	Light Pillar works around this issue, making it possible to "absorb" the bulk of the rainbow attack with reserve energy. The only current useful application of this is with Varia Suit, and either 0 Energy + 3 Reserve, or 1 Energy + 2 Reserve. The short version is that it does this by setting up a delayed variant of "R-Mode Forced Stand" which is triggered after reserve auto-refill has already filled several points into main Energy.
		+
		+	The Crystal Flash has no technical value beyond being necessary to replenish the reserve tank following R-Mode entry (which otherwise has no reserves).
		+
		+	The X-Ray HDMA object has a value that tracks the current "X-Ray" stage. When X-Ray is not in use, it is in stage 0. While active it is in stage 2, and when the object is waiting to finish X-Ray cleanup, it is in stage 5. Stages 0-2 will jump to stage 3 (which proceeds to 5 over the next two frames) when dash is not pressed. Important to note is that this "stage" variable is a single global variable: when multiple X-Ray objects exist, they share this single value, which becomes relevant in the Light Pillar setup:
		+
		+	* At the start of the Light Pillar setup, Samus is in a typical "R-Mode" state, which has an X-Ray HDMA object, and X-Ray in stage 5, where it is stuck because time is not frozen.
		+	* Upon pressing X-Ray, a second X-Ray HDMA object is created and sets the X-Ray stage back to 0. It progresses to 2 while X-Ray is held.
		+	* Dash is released for one frame. In that one frame, the first object (in stage 2) observes run is not held and sets the stage to 3. The second object (now in stage 3) performs some cleanup, and moves to stage 4.
		+	* The next frame, dash is re-grabbed. As X-Ray is in stage 4, the first object will perform further cleanup and move to stage 5. The second object will now observe stage 5 and time is frozen, so it will perform the final cleanup and delete itself, which includes resetting the x-ray stage to 0 as well as unfreezing time.
		+	** At this moment, if X-Ray was still selected on the HUD, this would result in activating another X-Ray object, resetting to stage 0 and would be back to the previous item.
		+	* At this point, had run not been held, the remaining object would observe stage 0 and run not held, so it would jump to stage 3, progress to 5, and now you would be back to the normal "R-Mode" condition. However, because run was held, the object will instead progress through stage 1 and 2, believing X-Ray to still be active.
		+	* Stage 1 is responsible for "widening" the x-ray beam, but it is worth noting that as part of the stage 5 cleanup, the X-Ray "angle" value has been set to 0, where normally it would be 40h or C0h depending on which way Samus is facing. This results in the X-Ray beam being aimed "straight up".
		+	* As the extra X-Ray object has unfrozen time, Mother Brain now can proceed to wind up the Rainbow Beam attack. It will connect and begin draining energy as normal.
		+	* 99 frames later, Samus's energy hits 0. Auto-reserve activates, freezes time, and begins refilling energy, while rainbow beam is paused.
		+	* After some amount of energy, dash is released. X-Ray progresses through stage 3 and eventually reaches stage 5.
		+	* With stage 5 and time frozen by reserve, the X-Ray performs final cleanup, which unfreezes time, allowing rainbow beam to resume while Reserve Tank is still filling, performing the normal "R-Mode Forced Stand" situation, but delayed by several frames due to having held dash previously.
		+	* Because the main energy tank was allowed to populate some energy, the net result is that auto-refill is replenishing energy as quickly as rainbow beam drains it: this results in the appearance that the energy counter has stopped (as if you were taking no damage): in truth, the damage is being taken straight out of the reserve tank.
		+	* Rainbow Beam will generally finish before auto-reserve does, so Samus will fall in the "downed" pose while reserves finish filling up.
		+
		+	Because Light Pillar delays the R-Mode Forced Stand, it does not benefit from "clipping" the bottom of Samus's energy tank twice, as the normal suitless R-Mode tactic does. Thus, a no-Varia attempt would reduce only 1 point of energy lost instead of 2. Thus it does not allow Samus to survive Rainbow Beam with one fewer tank, but it would allow some combinations that would not work with normal R-Mode. For example, while standard game does not have more than 4 reserve tanks, a 1+5 option is possible which may be of relevance in hacks/randomizers.

	====FX-dependent HDMA objects====		====FX-dependent HDMA objects====

@@ Line 61: / Line 61: @@
 ===X-Ray HDMA object===
-The continued presence of the X-Ray HDMA object is what allows for an auto-reserve trigger to cause the R-mode forced stand-up. The X-ray state ($0A7A) ends up stuck with a value of 5, which is the final X-Ray deactivation state. In most cases, this HDMA object also causes the "colour math subscreen backdrop colour" to get overwritten on each frame ($88870C), to the gray color associated with how X-Ray dims the screen. This interferes with the operation of a Crystal Flash, which uses the "color math subscreen backdrop colour" as a sort of counter (at $88A35D). As a result, after using a Crystal Flash in G-mode, usually the Crystal Flash clean-up at $88A317 fails to occur, and this means that the power bomb explosion status ($0592) remains set to $8000 after the Crystal Flash completes, and the two HDMA objects created by the Crystal Flash also remain. This leaves behind a "light orb" which can continue to damage enemies. The game audio will also be silenced (why?).
+The continued presence of the X-Ray HDMA object is what allows for an auto-reserve trigger to cause the R-mode forced stand-up. The X-ray state ($0A7A) ends up stuck with a value of 5, which is the final X-Ray deactivation state. In most cases, this HDMA object also causes the "colour math subscreen backdrop colour" to get overwritten on each frame ($88870C), to the gray color associated with how X-Ray dims the screen. This interferes with the operation of a Crystal Flash, which uses the "color math subscreen backdrop colour" as a sort of counter (at $88A35D). As a result, after using a Crystal Flash in G-mode, usually the Crystal Flash clean-up at $88A317 fails to occur, and this means that the power bomb explosion status ($0592) remains set to $8000 after the Crystal Flash completes, and the two HDMA objects created by the Crystal Flash also remain. This leaves behind a "light orb" which can continue to damage enemies. The game audio will also be silenced, as the game skips queuing new sounds (at $809075) while the power bomb explosion status is set.
 When the power bomb explosion status ($0592) remains set to $8000, this prevents the use of X-Ray (due to the check at $91E1AA). Leaving the room or triggering auto-reserves will clear the power bomb explosion status ($0592) and allow the use of X-Ray again. Laying another Power Bomb is also an option that can work in some rooms, depending on how many HDMA objects are already occupied by the room's FX (described in some detail below). However, laying another Power Bomb has a side effect of making the foreground (BG1) disappear (why?); in this case, the foreground can be viewed temporarily by using X-Ray, and will be restored permanently by leaving the room.

@@ Line 7: / Line 7: @@
 * palette FX flag ($1E79) is cleared to 0 (at $91E23D).
 * an X-Ray HDMA object is created (at $91CAEE) which handles the control of the X-Ray beam, along with its deactivation once dash is released.
-* the input handler is changed to $90E918 (at $91EF07).
+* the input handler ($0A60) is changed to $90E918 (at $91EF07).
 During normal usage of X-Ray, these changes create the intended effect that time has stopped, allowing the playing to inspect the room with X-Ray without having to worry about dodging enemies, their projectiles, or other hazards, and the player can turn around to scan on either side but cannot move. Note that the game state ($0998) remains in "main gameplay" ($08) the whole time; just the modifications to the flags affect the behavior of the game.
@@ Line 47: / Line 47: @@
 ===X-Ray Input Handler ($90E918)===
-This handler replaces the normal ($90E913) input handler, which has the effect that most normal controller inputs stop functioning. During normal X-Ray use, this handler allows Samus only to turn around, allowing the X-Ray beam to be aimed in all directions.
+The location $0A60 contains a pointer to the routine that handles (most) player input. This is an address into bank $90 and most of the time it is either $E913 or $E926, which provide for normal gameplay. During X-Ray startup, it is set to $E918 which instead is a limited input routine used for the X-Ray Scope. This has the effect that most normal controller inputs stop functioning.
-The X-Ray input handler looks only at 3 conditions: whether or not Samus is crouched, which direction Samus is facing, and whether or not the opposite D-Pad button is pressed. (The effect of up/down moving the X-Ray beam is handled by the X-Ray HDMA object.) This results in the G-Mode Immobile state: Samus can turn around, but can do nothing else.
+The X-Ray input handler looks only at 3 conditions: whether or not Samus is crouched, which direction Samus is facing, and whether or not the opposite D-Pad button is pressed. During normal X-Ray use, this allows Samus to turn around, allowing the X-Ray beam to be aimed in all directions, but do nothing else. (The effect of up/down moving the X-Ray beam angle is handled by the X-Ray HDMA object.)
-The handler is restored to normal at one of two places relevant to G-Mode:
+Because the handler is not restored to normal when the X-Ray deactivation is not performed, this results in the G-Mode Immobile state: the only actions possible are to turn around in place, or to (re)activate X-Ray.
-Once the handler is restored to normal, G-Mode Mobile has been entered and Samus can now move normally. However, during G-Mode Immobile there is one more unique effect: G-Mode Morph. This happens because when the X-Ray input handler sees that a direction opposite the current facing direction is pressed, it changes Samus into a "Turning around" pose: a crouching version if Samus was crouched, and a standing version otherwise. During normal X-Ray use, Samus would only ever be crouching or standing, but if the opposite direction is pressed during knockback frames, then it enters the "Standing turnaround" pose (because a knockback pose is not crouching). This pose looks at the previous pose in order to determine if Samus should turn around with the Arm Cannon aimed upward or downward by looking at which way shots would have fired before, but the previous pose - the "knockback" pose - cannot fire shots at all. This results in a table overrun that reselects the pose from a piece of code located in the walljump pose setup, which happens to correspond to the "Entering morph, facing left" value. This results in Samus entering the Morph Ball state, while facing left. G-Mode Morph does not, itself, reset the input handler, so you still have to wait for the knockback frames to run out before you can move.
+The handler is restored to normal (specifically, $E913) at one of two places relevant to G-Mode:
 ===X-Ray HDMA object===

@@ Line 45: / Line 45: @@
 When this flag is cleared, it prevents processing of palette FX, such as the glowing colors in Wrecked Ship, Red Brinstar, and hot Norfair rooms. More significantly, it prevents heat damage, giving the "artificial Varia" effect.
-===X-Ray Input Handler ($90E918)====
+===X-Ray Input Handler ($90E918)===
 This handler replaces the normal ($90E913) input handler, which has the effect that most normal controller inputs stop functioning. During normal X-Ray use, this handler allows Samus only to turn around, allowing the X-Ray beam to be aimed in all directions.

@@ Line 7: / Line 7: @@
 * palette FX flag ($1E79) is cleared to 0 (at $91E23D).
 * an X-Ray HDMA object is created (at $91CAEE) which handles the control of the X-Ray beam, along with its deactivation once dash is released.
-During normal usage of X-Ray, these changes create the intended effect that time has stopped, allowing the playing to inspect the room with X-Ray without having to worry about dodging enemies, their projectiles, or other hazards. Note that the game state ($0998) remains in "main gameplay" ($08) the whole time; just the modifications to the flags affect the behavior of the game.
+During normal usage of X-Ray, these changes create the intended effect that time has stopped, allowing the playing to inspect the room with X-Ray without having to worry about dodging enemies, their projectiles, or other hazards, and the player can turn around to scan on either side but cannot move. Note that the game state ($0998) remains in "main gameplay" ($08) the whole time; just the modifications to the flags affect the behavior of the game.
-Normally, all of these changes are undone during the X-Ray deactivation routine ($91E2AD). However, if an auto-reserve trigger finishes while X-Ray is active, then this restores the time-is-frozen flag ($0A78) to 0 (at $82DC18), which prevents the X-Ray deactivation from completing, as it checks (at $888A26) that time is frozen as a condition for the deactivation to proceed. This leaves the game in the "G-mode" state, where processing of PLMS, enemy projectiles, animated tiles, and palette FX remain disabled. The X-ray HDMA object also remains, and as a result, every frame it continues to check the time-is-frozen flag to see if it should proceed with the X-Ray deactivation cleanup; if auto-reserves are triggered again, this will happen, resulting in Samus being forced to stand up ("R-mode forced stand-up") and an end to the G-mode effects. The forced standup occurs because part of the X-Ray deactivation involves putting Samus into a standing pose (at $888A5A).
+Normally, all of these changes are undone during the X-Ray deactivation routine ($91E2AD). However, if an auto-reserve trigger finishes while X-Ray is active, then this restores the time-is-frozen flag ($0A78) to 0 (at $82DC18), which prevents the X-Ray deactivation from completing, as it checks (at $888A26) that time is frozen as a condition for the deactivation to proceed. This leaves the game in the "G-mode" state, where processing of PLMS, enemy projectiles, animated tiles, and palette FX remain disabled, and the x-ray input handler remains active. The X-ray HDMA object also remains, and as a result, every frame it continues to check the time-is-frozen flag to see if it should proceed with the X-Ray deactivation cleanup; if auto-reserves are triggered again, this will happen, resulting in Samus being forced to stand up ("R-mode forced stand-up") and an end to the G-mode effects. The forced standup occurs because part of the X-Ray deactivation involves putting Samus into a standing pose (at $888A5A).
-While in G-mode, if X-Ray is used again, a second X-Ray HDMA object will be created; when X-Ray deactivates, this second X-Ray HDMA object will be deleted, and the enemy projectile, PLM, animated tiles, and palette FX flags will all return to normal, ending G-mode. However, the first X-Ray HDMA object will still remain, meaning the "R-mode forced standup" is still possible. So "R-mode" is simply the result of entering G-mode and then using X-Ray again. Normally this is done by continuing to hold X-Ray through to the end of the auto-reserve trigger, which buffers a second use of X-Ray after the reserve trigger finishes; however, in terms of the resulting game state, there is no difference between doing this vs. entering "G-mode" and then using X-Ray at a later time in the same room.
+While in G-mode, if X-Ray is used again, a second X-Ray HDMA object will be created; when X-Ray deactivates, this second X-Ray HDMA object will be deleted, and the enemy projectile, PLM, animated tiles, palette FX flags, and input handler will all return to normal, ending G-mode. However, the first X-Ray HDMA object will still remain, meaning the "R-mode forced standup" is still possible. So "R-mode" is simply the result of entering G-mode and then using X-Ray again. Normally this is done by continuing to hold X-Ray through to the end of the auto-reserve trigger, which buffers a second use of X-Ray after the reserve trigger finishes; however, in terms of the resulting game state, there is no difference between doing this vs. entering "G-mode" and then using X-Ray at a later time in the same room.
 When leaving the room in G-mode, the X-Ray HDMA object will get cleaned up (at $82E2FA), ending the "R-mode" effects, but the enemy projectile, PLM, animated tiles, and palette FX flags will remain disabled, preserving the G-mode effects.
@@ Line 43: / Line 44: @@
 When this flag is cleared, it prevents processing of palette FX, such as the glowing colors in Wrecked Ship, Red Brinstar, and hot Norfair rooms. More significantly, it prevents heat damage, giving the "artificial Varia" effect.
 ===X-Ray HDMA object===

@@ Line 56: / Line 56: @@
 * Kraid Room
 * Crocomire's Room
-* Phantoon's Room
+* Phantoon's Room (only if the room was entered with Phantoon alive)
-* Draygon's Room
+* Draygon's Room (only if the room was entered with Draygon alive)
 * Mother Brain Room
-Therefore, when Crystal Flash is used in these rooms in G-mode/R-mode, it will clean itself up normally, and not leave behind a light orb or prevent the use of X-Ray. The game checks for "Statues Room" and "Glass Tunnel" directly by comparing the room pointer to the two specific values; it checks for boss rooms by comparing the boss ID ($179C) to the 5 specific values. Technically it also checks for fireflea rooms (by looking at the FX type $196E) and will avoid overwriting the "colour math subscreen backdrop colour" in these rooms as well; however, the fireflea effect itself overwrites these color values, hence the Crystal Flash will fail to be cleaned up, leaving behind a "light orb" in fireflea rooms the same as in other rooms.
+Therefore, when Crystal Flash is used in these rooms in G-mode/R-mode, it will clean itself up normally, and not leave behind a light orb or prevent the use of X-Ray. The X-ray handler checks for "Statues Room" and "Glass Tunnel" directly by comparing the room pointer to the two specific values; it checks for boss rooms by comparing the boss ID ($179C) to the 5 specific values. The boss ID is set by enemy initialization for the boss, which in the case of Phantoon and Draygon only happens if the bosses are alive when entering the room (because the room states for these rooms do not include any enemies in the state where the boss is dead). Technically the X-Ray handler also checks for fireflea rooms (by looking at the FX type $196E) and will avoid overwriting the "colour math subscreen backdrop colour" in these rooms as well; however, the fireflea effect itself overwrites these color values, hence the Crystal Flash will still fail to be cleaned up, leaving behind a "light orb" in fireflea rooms the same as in other rooms.
 ====FX-dependent HDMA objects====

@@ Line 48: / Line 48: @@
 The continued presence of the X-Ray HDMA object is what allows for an auto-reserve trigger to cause the R-mode forced stand-up. The X-ray state ($0A7A) ends up stuck with a value of 5, which is the final X-Ray deactivation state. In most cases, this HDMA object also causes the "colour math subscreen backdrop colour" to get overwritten on each frame ($88870C), to the gray color associated with how X-Ray dims the screen. This interferes with the operation of a Crystal Flash, which uses the "color math subscreen backdrop colour" as a sort of counter (at $88A35D). As a result, after using a Crystal Flash in G-mode, usually the Crystal Flash clean-up at $88A317 fails to occur, and this means that the power bomb explosion status ($0592) remains set to $8000 after the Crystal Flash completes, and the two HDMA objects created by the Crystal Flash also remain. This leaves behind a "light orb" which can continue to damage enemies. The game audio will also be silenced (why?).
-When the power bomb explosion status ($0592) remains set to $8000, this prevents the use of X-Ray (due to the check at $91E1AA). Leaving the room, triggering auto-reserves, or laying another Power Bomb will clear the power bomb explosion status ($0592) and allow the use of X-Ray again. However, laying another Power Bomb has a side effect of making the foreground (BG1) disappear (why?); in this case, the foreground can be viewed temporarily by using X-Ray, and will be restored permanently by leaving the room.
+When the power bomb explosion status ($0592) remains set to $8000, this prevents the use of X-Ray (due to the check at $91E1AA). Leaving the room or triggering auto-reserves will clear the power bomb explosion status ($0592) and allow the use of X-Ray again. Laying another Power Bomb is also an option that can work in some rooms, depending on how many HDMA objects are already occupied by the room's FX (described in some detail below). However, laying another Power Bomb has a side effect of making the foreground (BG1) disappear (why?); in this case, the foreground can be viewed temporarily by using X-Ray, and will be restored permanently by leaving the room.
 At $888700, the X-Ray HDMA handler calls a function $91D143, which checks if one of a few special situations applies where the X-Ray HDMA handler will not overwrite the "colour math subscreen backdrop colour", unlike most rooms. These exceptions are the following rooms:
@@ Line 64: / Line 64: @@
 * Mother Brain Room
-Therefore, when Crystal Flash can be used in these rooms in G-mode/R-mode, it will clean itself up normally, and not leave behind a light orb or prevent the use of X-Ray. The game checks for "Statues Room" and "Glass Tunnel" directly by comparing the room pointer to the two specific values; it checks for fireflea rooms by looking at the FX type ($196E); and it checks for boss rooms by comparing the boss ID ($179C) to the 5 specific values.
+Therefore, when Crystal Flash is used in these rooms in G-mode/R-mode, it will clean itself up normally, and not leave behind a light orb or prevent the use of X-Ray. The game checks for "Statues Room" and "Glass Tunnel" directly by comparing the room pointer to the two specific values; it checks for fireflea rooms by looking at the FX type ($196E); and it checks for boss rooms by comparing the boss ID ($179C) to the 5 specific values.