i would not consider it as bad, just "not finished"..
i played some and i think the controls need some work or im just too stupid for it. but i like the rest so far, i didnt made much yet or got very far. but i like it for now and i thinks its pretty worth it to get if u liked terraria.
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but its pretty hard i have to say, i died in like 1-2hours play time more than i did in like 100 hours terraria :|