Hi! Thanks for letting us know! Glad you enjoyed the game. I totally get what you said about the ending - it definitely could've been better and the game kind of ends abruptly.
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Well, that was just a remarkable idea from a player - not our original thought. But I really like that it's open to interpretation.
Let me put on my pseudo science glasses: the original idea behind the darkness entity is that it's not a "monster" or an illusion but some sort of "field" that sucks everything into it, and what you hear is actually those on the other side of it that are screaming for help. The "pill" is actually a crystal that "generates" a negating field of some sort that negates the "dark field" of the entity.
Obviously we hadn't thought about it that much at the beginning - we just thought it'd be cool to beat the darkness after escaping it for 13 levels, and that it'll be nice to have something vague that interacts with it. :D
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By the way, seeing that people still play this two years after we published it is amazing. Thank you :)
Cheers!