I really love the proposed implementation of the Force Nightmare (could probably use a better name though). It is thoroughly unique, seems very useful in certain situations (need to deal lots of damage quickly and don't care about long-term consequences), and isn't actually weak to ethereal attacks (you can only deal 1 damage to it each turn, so ethereal is overkill). It manages to be both frightening and balanced (at least conceptually): the enemy absolutely needs to deal with it or it is going to wreak havoc, but if the enemy can outlast it then he/she will have the advantage.
I'm not sold on the Nightmare Eater. The idea is fine, but having the sleep roll be a separate attack, need a 9+ (making it unlikely to land most of the time), and having +2 upkeep seems like overkill. That's going to end up making the creature rather ineffective, because it's going to have to waste 1-3 turns (on average) and 2-6 mana just to set up for a single powerful attack (which an opponent can prevent by merely attacking whatever you just put to sleep). It would be a lot more attractive if the sleep roll was combined with the attack, and only needed a 7+ (putting the odds at 50/50). That would certainly justify the +2 upkeep.
Nightmare Knight (Knightmare) is interesting. I like the idea of perpetual daze. However, wouldn't it be more thematic for the Knightmare to regain health when daze counters are not removed (as in, its ability is working) as opposed to when its ability fails? Or are you worried that would make the creature too swingy (either you are getting lucky and near invincible or you get unlucky and die immediately)? I know you said you haven't properly balanced these ideas, but you might need to buff it up a bit as well (and/or lower the upkeep cost). A Whirling Spirit, while lacking the daze functionality, possesses both significantly more health and a better attack than the Knightmare does (plus only has an upkeep of 1). I also think there's not enough incentive to play more than one of these at a time. If the Knightmare is supposed to be a solid mid-tier Mind/Dark creature (like the knights of other schools), then it should be designed in such a way as to encourage (or at least not discourage) players to summon more than 1 at a time. The passive ability of preventing the removal of daze tokens is the creature's best trait, and it makes no difference whether there are 1 or 4 of them in a zone.
All in all, some very interesting ideas. I look forward to seeing what creature ends up being the winner.
I like all the creatures, but I don't quite see the connection to the ideas posted - laddin, do you want to talk to your inspiration/concept development a little?
I have the same feeling, these are interesting but but seems new ideas...
I see some resemblance to past suggestions, but Laddinfance has clearly also modified and put new spins on them. I actually like that (it interests me to see different points of view on existing ideas), but I can understand if you feel differently. In general, when submitting ideas for things it is rare for those ideas to remain completely unchanged.
