Ryo Gate Skip
Note: This page describes a glitch, trick, or exploit. To see others, click here.
North Ryoshima Coast is separated from Ryoshima Coast by a tall gate, which is topped with an even higher invisible wall. Normally, to get past the gate, one must obtain the Border Key key item from talking to Queen Himiko, then talk to one of the guards in front of the gate. It's possible to skip the first meeting with Himiko (normally done via Fire Tablet Skip) by going over or around the gate to reach the loading zone behind it.
In general, such a skip only needs to be performed once, as the gate will open automatically during the Oni Island sequence. You can also activate the True Mirrors or Mermaid Springs inside North Ryo to maintain access without the Border Key.
By using KTs you can jump over the gate towards North Ryoshima Coast. Simply run up towards the gate, do two KTs and end on a dash to get over the invisible floor above the gate, landing in the loading zone.
Via Slope KT's (NG+ 2017)
Even without mid-air KT's, it's possible to perform slope KT's off the cliff-face directly East of the gate in order to get around the right side of the gate collision.
It's possible to clear the gate's collision by performing a very difficult and precise sequence of Sliding Ground Tackles (SGT's) along the cliffs East of the gate. The rocky cliffs around Ryoshima Coast are all flagged as Jump Barrier collision, meaning Ammy cannot jump if she is vertically above a cliff polygon, no matter the height. As such, the only effective way to traverse them is to land on a slope on the cliffs, SGT such that Ammy slides off, and jump late enough that Ammy is no longer above the Jump Barrier collision. Then, you can double jump back onto the cliff to repeat, until one reaches the point where the gate can be cleared.
To get onto the cliff collision, one must first get onto the other gate near Sei-an City. This can be done by double jumping at it at an angle, then immediately jumping on top of it. From there, you jump toward the cliff onto a large, triangular piece of invisible collision called the "magic triangle". With gold dash, one can jump almost straight to the left at the left edge of the triangle, then jump forward and to the right onto a sloped piece of cliff. SGT at the edge of that slope, then do a very delayed jump, and a quick double jump back onto the back side of the same jutting-out piece of the cliff. SGT again, and (optionally) use the brush to re-adjust the camera angle. Delay the double jump very slightly to avoid the hard-landing animation Ammy receives when landing with high vertical speed. Perform a final SGT and double jump to land on top of the gate collision. Jump and air tackle into the loading zone.
Demonstration: https://youtu.be/9cJHwN13zWg (See description)
The NG+ 2017 variant of this trick (using slope KT's) was discovered by DreamRifty on 06 December, 2020.
The NG variant of this trick (Barrier Skip) was first theorized by LegoerofEggos the evening of 03 April, 2021 (https://twitter.com/legoerofeggos/status/1378575443159212033?s=20), and first demonstrated by Popprocks the following morning.