Height Lock No Clip
Note: This page describes a glitch, trick, or exploit. To see others, click here.
Explanation
"Height lock no clip" (HLNC) is a glitched state of physics in which Amaterasu is seemingly stuck at her current height, and can freely travel through any terrain unobstructed. HLNC can be obtained by using Walking While Talking to cancel a cutscene after it sets the appropriate flag(s) to HLNC, thus ending the cutscene before it resolves the game state back to normal. As a result, Amaterasu will keep the HLNC state in the overworld, and can retain it while moving around, passing through loading zones, and even through cutscenes which do not unset the HLNC flag. Amaterasu can use the brush during this state, but cannot enter the fan menu. This state also causes many NPCs to T-pose assertively.
Process
The two currently known methods of acquiring HLNC both occur around the same location in the game: one in Tsuta ruins, and the other in Agata forest.
In Tsuta ruins, you can store the poison spewing pots cutscene by doing Pot Skip. Use that cutscene to store Issun's text box asking if you are sure you wish to leave Tsuta ruins. Then, enter the vine room and trigger the vine constellation. Cancel the cutscene by closing Issun's dialogue with the left option. You will load into Agata Forest with Height Lock No Clip. This HLNC method renders the vine brush power unobtainable, and thus the game cannot be beaten due to the Ark Spider Queen boss fight. Demonstration: https://youtu.be/zAR6IOG7cys?t=11705
In Agata Forest, you can overlap the cutscene of a cabbage or walnut being delivered to Sleepy, with the cutscene of opening the chest with Rosary Beads. Wait until day transition to unfreeze the cutscene state, then brush to regain full control. You will need to manipulate the cutscene state slightly here in order to regain normal functionality of the talk button, which can be achieved by blooming a cursed patch or by reading the sign near the mermaid spring. During the day time you can talk to Kokari to get a floating text box, then tackle him until he cries, then talk to him once more. This will give you a floating text box that will load you into fishing when it closes. Wait for another day transition so you can regain movement. You may then feed any wildlife in Agata Forest, such as the rabbits near HBS or the rabbits near Madame Fawn. The feeding cutscene will enter Height Lock No Clip, and will be interrupted by loading into fishing. You may then exit out of fishing and load into Agata Forest with HLNC. As covered in the next section, you may need to walk into and out of Tsuta Ruins to regain your shadow, and you may then proceed with HLNC.
Mechanics
Height Lock No Clip negates all collision, and Amaterasu can easily travel through walls, floors, into and out of demon scroll fights, and infinitely into the void. Amaterasu will move much faster with HLNC if you tackle jump prior to travelling, as tackle jump speed is significantly better than walking speed or falling speed. In most areas of the game, walking off the floor will result in Amaterasu entering a falling animation and floating into the void. However, in some areas such as Kamui and Ezofuji, Amaterasu can easily be manipulated to walk on an invisible floor in the void.
Amaterasu's shadow has unusual importance during HLNC. Under normal conditions where her shadow is present, you can jump and land on floors easily by tackle jumping, traveling at will, and air tackling to land back on the floor. However, when Amaterasu's shadow disappears, the mechanics of HLNC will change in troubling ways. When travelling over water, the shadow will disappear and Amaterasu will no longer be able to land on ground. When travelling over snow, Amaterasu's shadow will disappear, and she will get stuck on an invisible floor and be unable to gain or lose any height using the movement strategies that are available. It is generally wise to travel out of bounds in areas with water or snow, to avoid losing your shadow.
If you lose your shadow (such as because you gained HLNC from fishing and you are surrounded by water), you may regain it by travelling through a loading zone. The Tsuta ruins loading zone can be reached after exiting fishing. You can also reach Yoshpet upon entering healed Kamui mainland (after the 3rd tunnel), which may help with getting close to Wep'keer with your shadow.
Changing Height
Despite that Height Lock No Clip is designed to freeze your Y value, there are some methods you can use to both gain and lose height. There is a very slow method to both gain and lose height, which is performed by initiating a tackle while running and turning. If you are moving forward and sharply turn to the left a few frames before tackling, Amaterasu will gain a slight amount of height while winding up the tackle. Conversely, if you are moving forward and turn to the right and initiate a tackle, Amaterasu will lose a small amount of height. When done perfectly, you can change your Y value by about 0.6 per tackle. If Amaterasu is not turning enough when tackling, the Y value will change by even smaller amounts. This method will take hundreds of tackles to gain or lose meaningful height. The most notable example of this is lowering yourself from the first tunnel in Kamui down to the loading zone of the 2nd tunnel, which requires a change of -80 Y value. This takes around 125 perfect tackles, or multiple hundreds of imperfect tackles. This process is likely to take between 15 and 40 minutes depending on how efficient the player's method is. There is no other known method to lose height, but there is a faster method to gain height.
Amaterasu can gain height by jumping and tackling into an upward slope. Upon landing, Amaterasu will snap slightly to the higher slope, and can gain a few units of Y value. Furthermore, Amaterasu can also tackle from behind a slope (out of bounds under the slope), and tackle backwards inbounds onto the slope, which will gain even greater height. Tackling from behind the slope inbounds and landing can gain as many as 8+ Y units per maneuver. Therefore, it is relatively trivial to gain height with HLNC so long as there is a slope you can climb.
Using these movement techniques, it is possible to take a Height Lock No Clip from Agata Forest all the way to the Ark Of Yamato. This strategy requires you to enter and bloom Kamui prior to gaining HLNC, because blooming Kamui will end HLNC as discussed in the next section.
Ending HLNC
While many loading zones and cutscenes do not end HLNC, there are some notable situations which will cancel it. Blooming a guardian sapling will end Height Lock No Clip, which restricts its usefulness in entering cursed areas. For example, it is not helpful to travel from Agata Forest to Cursed Taka Pass; or Agata Forest to Healed Taka Pass to Cursed Ryoshima Coast. While Amaterasu can travel through the cursed areas without restriction, there are no loading zones until you heal the area.
Amaterasu can enter and leave normal encounters at will, but many encounters with loading zone cutscenes will untrigger HLNC. Some examples of fights that end HLNC include Waka 2 and Igloo Turtle.
Entering the Tango Cutscene to the Ark Of Yamato will cancel HLNC, which is beneficial as it's much faster to defeat bosses in the ark with access to the fan menu (exorcism slips).
Many other cutscenes and loading zones will not end HLNC. Some examples of cutscenes which *DO NOT* cancel Height Lock No Clip include entering a major area for the first time (camera pan and issun dialogue), in-game dialogue cutscenes (such as talking to Samickle in Wep'keer), or entering Ark of Yamato through the direct loading zone behind the Tango Cutscene.
Applications
p0ppr0cks has used HLNC in a segmented New Game Minimum Brushes run, to travel from Agata Forest all the way to the Ark of Yamato. This skips Blizzard, and the requirement to have Fireburst or Inferno to melt the slots. The notable segment using HLNC: https://www.twitch.tv/videos/1498542695
While HLNC can be achieved very early in a New Game file, it is difficult to implement in speedruns due to the fact that it is difficult to make significant progress in cursed areas while maintaining HLNC. You could use HLNC to heal Kamui very early on, and could enter Wawku Shrine or regain HLNC and use it to reach Ark. However, you cannot progress in Wawku Shrine without a fire brush power, and you cannot beat bosses in Ark without having necessary brush powers such as Thunderstorm, Galestorm, and Vine.
Furthermore, gaining HLNC and travelling with HLNC is somewhat time consuming.