龘 means 'the appearance of a dragon walking', which is such an evocative phrase! It always makes me wonder: is there a separate kanji for 'the appearance of a dragon breathing fire?' ... It's also one of the first non-Jōyō kanji I learnt, and one of the highest stroke counts (48) there is.

Jonathan Kirk, founder of the Kanshudo system for learning Japanese: https://www.kanshudo.com