Out of all the Final Fantasy monsters there are, my absolute favourite is the Malboro. I think they scratch the same itch as Beholders and their kind (and indeed, in my game world are a kind of cheldean abomination). Anyway, here is my 5e take on them. It HEAVILY uses the conditions I detailed HERE, so make sure you have a copy of that if you decide to use these things.
Hope you like. Enjoy!