Ah yes dermagnus has a thing for nightmare, and gheist for that matter.
yh idk i'm not gr8 with gheist and nightmare cause i'm terrible at making threats to my opponent but idk the powers not gr8 in either of them so you might struggle against roots and piranas as well as 1pillvs1pill play but i guess the main thing is if you are good at making those ko threats to your opponent and you like the deck then be my guest and buy it.
p.s no1 like harlequins come on you saints
I hardly ever use damage reducers. I do not feel I need them... which is probably a matter of play style. I don't remember a single instance where I said "Oh how I would love having a damage reducer now". (Anecdote: the one time I love having one was when I spent 5 pills on Gina Glitt and sureshotted my opponent with her. That was funny :O). Conversely, when I play nightmare, opponent damage reducers often get "quasi-ignored". Have a min 2? Play that Hel and still get full damage or something. It goes back to playing style. Nobody can help you there. I say one does not need damage reducers. Others disagree. Still others build decks _around_ damage reduction. There you go; switch on own thinking.