I'm playing around with Nightmare since Essence's Day Traitors works so well.
This is what I came up with. It's still not perfect, but fun to play
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5ie 5ie 5ie 5ie 5ie 7gk 7gk 7gk 7gk 7gk 7gk 7gk 7gk 7gk 7gp 7gp 7gp 7h1 7h1 7h1 7mt 7mt 7mt 7mt 7mt 7th 7th 7th 7th 7th 8pt
Usually I play it like this:
If a Shield is drawn early, save the quanta for them (don't do this if you play against fire or darkness...)
Nightmare Damselflies and kill all creatures with more than 2 Atk with Toadfish.
Play Inundation.
(Because it draws Quanta don't play it early. But if the enemy really has lots of creatures and Toadfish isn't fast enough you can use it).
If you don't have a Shield try to play ASAP Toadfish and Damselflies to kill creatures
and wait for your shield. Also you don't have to hold your fly in your hand if the enemy plays weak creatures (you can nightmare those).