I feel like I could use an answer key after solving some of them levels. For instance... (after some spoiler space, so it'll get hidden by a "read more")
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- Level 7: It seems to involve dropping a letter from one end or the other, but then why doesn't DISCO become DISC?
- Level 17: Clearly the vowel changes, but why STACK and not STUCK/STOCK? Why NUT and not NET? (Similarly for the three after it.)
Starting to get a little leery by level 22, where it feels like a guessing game. (Why SOFT and not EASY as the four-letter opposite of HARD? And POSSIBLE isn't particularly the opposite of FACTUAL; it's kind of the opposite of "definite", while "fictional" or "made-up" or otherwise definitely not true is the opposite of "factual".
In fact, currently stuck on level 23, where SEVER sure looks like it follows the rule of "synonym starting with S"...I really love the concept here, but the rules just aren't strict enough in some cases to know what the answer is. (Maybe it could use more hint options than "the first letter or the whole word"?)