I checked out the hold, and I found a backtracking error in Level 1: 1N1E, where the wubba character that Beethro uses to open the door to the East doesn't respawn after that cutscene is done.
So if you try to head West or South instead of going East immediately, the wubba won't respawn and I'm pretty sure Beethro can't hit that switch by himself.
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Also, it's possible the scrolls might explain this, but in Level 1 5N I didn't like how the mimic appeared out of nowhere once Halph entered the hot tile area. In general, most people prefer it if they can see a pressure plate or a power token and fuse that would release the mimic, which they can see at the start of the room and understand immediately how it works.
Then they know that they're supposed to go onto the hot tiles without having to guess that the architect wanted them to do it.
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I like the idea of having Halph come rescue Beethro, and I'm playing the rest of the hold to see how it turns out.
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