Another meta inspired by thinking about what effect its element would have on an answer word.
If you want to write your own puzzle that works like this, then well I'm sorry you'll need a variant, because we used up almost all the working answers. For maximum elegance, we wanted every step to be unique, which meant (1) common words only and (2) no alternate paths even through uncommon words. In the end, there is still a slight ambiguity with ADE, but this is apparently not a real word and didn't trip any testers.
Instead of "What burns on the Nth day?" we originally used N fire emojis. But we found that any straightforward way of communicating numbers led to testers indexing and reindexing and rereindexing, trying a dozen different interpretations with 3 out of 5 answers in the hopes that nutrimatic could fill one of them in. Big thanks to the tester who suggested the current phrasing.