This is a deck I came up with that takes advantage of the new card nightmare. The blank cards are Nightmares.
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5uk 5uk 5uk 5uk 5uk 5uk 5uk 5uk 5ul 5ul 5ul 5um 5um 5um 5um 5um 5um 5up 5up 5up 5up 5us 5us 5us 5v1 5v1 5v1 5v1 5v1 5v1 8pt
The idea is straight denial. I tested it against AI3 and was dominate but I never faced another darkness deck which would be a problem. Against a darkness deck you may be able to nightmare dragons if you can get one out and keep your opponents quanta low but otherwise you would be screwed.
Strategy:
Play devourers first. Then play nightmares so the opponent cannot draw for more towers. Then steal any towers they have out (or any pesky shields or weapons). Then when the opponent is locked down play the dragons and win.