Found another case where Tengu Strike won't cast:
If you try to cast it right after you enter a portal (casting it while the map is changing), you can't cast Tengu Strike in the map you moved into.
Thank you for your criticism, AaronHusky. I see that people are concerned about her becoming OP with the suggestions I proposed, which is understandable. I want to focus on the QoL parts of the suggestions. Changes could be made so that Kanna can b…