It definitely suffered from its share of technical problems. I read an article asking whether it was fair to hold two brothers writing an engine from scratch to the same standards as Bethesda/Rockstar/Ubisoft -- my own feeling was that no, it's not entirely fair. I just did what I do in the majority of games on my increasingly aged rig: drop all the settings down to just about minimum and play on anyway. But of course your mileage may vary.
Certainly, there were plenty of spots where you could practically see the developers' hands blocking one line of sight and opening another; and often enough I was able to "trick" the raycasting into giving me a pixel's worth of an opening in the leaves to map out an area I probably wasn't supposed to. But I've always had a thing for finding something new on a game world's horizon, and Miasmata feels like one of the first games built around specifically that.
[Also holy crap Milo is horrendously broken. I imagine it was put in to add a certain constant tension, but I'm not sure that was the best approach. And to my knowledge the achievements for beaning it with fruit and cans are still busted.
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