30 would fit in with the rest of the game, true, but unlike roaches or tar, it doesn't travel around corners. Maybe 10 is too much, especially if you want to introduce extra elements, but the balance needs to be made between challenge and interest.
Of course, if it is too often, you can't kill the damn thing. On its own, it doesn't justify the 30, but with other creatures, the 10 gets a bit tricky (but then you can use creatures to block the waves, so it don't matter).
We could make it like tar, but the soundwaves do kill themselves if they can't move, so the difference between making them compulsory and not is about 15 hits on the '5' key. I'd prefer it if Beethro didn't have to wait, as you can't kill the things, but it depends on how easy that is to code.
Well, the movement
should mean that the waves move in a square shape, but they'll leave a space when they pass solid objects. In reality, this won't happen, but I was thinking more along the lines of hiding behind objects to block wind, but I couldn't exactly call it a 'farter beast'.
As you say, the duplication is to ensure a square shape is maintained. If not, it just means the waves go off in one direction, leaving huge gaping holes and not being very difficult to dodge.
Matt
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