Lizard folk in disguise
It was...it took a while for the group to realize what anime they were in as well. Several folks were laid out on death saves. The constant stream of legendaries did take a bit of time to run through so many 9th-7th level spells you never get to see very often.Your "terrible, terrible idea" sounds like it was pretty fun!
It was also fun, as almost everyone knew at least one of the heroic spirits from DnD history. Having The Lord of Blades yell 'Traitor' at sage was a 'Oh crap' moment, as was when Kitiara called for her mount, Skie.