virtually all of this trapdoor puzzle relies on knowing that an arrow only prevents movement in 3 directions (out of 8).
xxx
xBx
...
if Beethro is standing on an up arrow, he can exit that arrow to ANY of the x directions.
xxx
.Bx
..x
if Beethro is standing on an arrow facing NE, he can exit that arrow to any of the x directions.
so the trick of the room is to find places where "
odd directions"
help, and
almost always, when you're standing on an arrow next to another arrow which points the same direction, you want to move to the other arrow...
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