The Great Plateau barrier

The thing to know about the Great Plateau kill fog and box is that they both disappear after you get the paraglider. The corresponding flag is called IsGet_PlayerStole2.

As it turns out, that GameData flag is only checked by 5 functions in the entire program. One of them is the AIDef:AI/PlayerNormal code which is responsible for handling events for the GameROMPlayer (Link) actor.

In that large AI function, the following piece of code can be seen:

if ( !isDebug1 && !isDebug2 )
{
  if ( !hasParaglider(0) &&
       (x < -1600.0 || x > -350.0 || z < 1400.0 || z > 2400.0) )
  {
    ...
    // 奈落開始待ち means 'wait for abyss start' (= voidout)
    return changeState(v1, "奈落開始待ち", 0);
  }
}

What this piece of code does is force Link to void out if (a) debug flags aren't set, (b) he doesn't have the paraglider, (c) Link's coordinates are not inside this rectangle:

It is a simple, hardcoded, coordinate-based check, and it is embedded in the core Player actor code, so glitching past it is impossible barring major bugs that would likely leave the game broken and unplayable.