I like this idea, but I have no idea what powers you get in Yume Nikki. Like with Lemeza, mock up a movelist and she'll get more support.
A little long, but I have a decent moveset right here. Since Yume Nikki isn't exactly the most combat-centric game, I took some liberties with the moves. I was going for a tricky sort of character with some high-risk attacks.
If anyone thinks they have a better idea for something, by all means I'd like to hear it.
Madotsuki (Yume Nikki)
A = knife. A simple stabbing attack
A> = frog head tongue. decent range, and if you hit with the tip, it pulls the enemy closer.
Av = Hand head (medamaude). Has significant starting lag, but hits through defenses. it grabs and throws, doing good damage and knockback.
A^ = Flute. deals close range damage, and sends musical notes traveling upwards, but has a little ending lag. The notes can travel through floors but travel slowly, don't hurt much, and don't last long.
S = poo hair. place a fly where you're standing. If an enemy touches it, it deals damage and causes them to flinch. There's a limit to how many flies you can put out.
S> = Midget power. places a tiny Madotsuki on the ground that walks forward and drags the enemy with it, doing damage as it goes. Press >S again to make it explode, otherwise it disappears shortly.
Sv = Counterattack. This can be done a couple of ways, but each is pretty much the same effect. One is by using the Triangle Kerchief power. If she's hit during the move, she turns invisible for a moment and reappears with the knife, doing a dramatic running slash through.
the second possibility is only if you aren't already using Uboa as some kind of support. Madotsuki pulls out the blonde girl as a human shield (or if that's annoying to animate, just transforms into her). If she's hit, UBOA. Uboa could either cause damage or paralyze whoever hit her.
A third possibility is for her to pinch her cheek, and if she's hit, her bed appears and she jumps out of it, damaging the person that hit her when the bed appears and damage+knockback when she pops out.
Sv (midair) = falls straight down head first with a bloody shockwave around her when she lands. A little lag after this move for her to get up, during which you might make her invulnerable.
S^ = Witch. Flies straight up in her witch costume and can glide around until you perform an aerial... Or until she hits the ground.
Other interesting things you may or may not implement:
Guard: Blanket power, wraps herself up in a big blanket.
If you intend to implement dashing attacks, hers could be her bicycle. Jolts forward a bit and crashes into the enemy.
Miscellaneous regular attacks, in case you think the A moves I mentioned are unbalanced or if you need to put in aerials, can also be
Cat form scratch, stoplight to freeze and knock down, her rolling "decapitated head" power, Her umbrella, or a snowball with the purple hat and scarf (or Yuki-onna).
The snowball in particular might make a nice air-to-ground projectile.
For a flinch animation you might want to use the "faceless ghost" power as reference and have her stumble back as her face vanishes momentarily and her
head spins around. If you're letting characters get knocked down, you can use her "decapitated head" for that.
I thought about the physics and animation in the game Jump Ultimate Stars (DS) as a reference for what this game might be like (as it's also essentially a smash clone), but I didn't copy off the game by any means,
and Madotsuki wouldn't play exactly like any character in any game in particular. I only thought of the way the game transitioned into elaborate character actions for even its fairly simple attacks, and how it took liberties
concerning the skills each characters have compared to the source material.
is a bit long-winded, but a good example of how the game plays (skip to about 0:48, the narrator is annoying)
I also thought a lot about Nayuki Minase from Eternal Fighter Zero (PC fighter) for her stance and animations, as Nayuki fights while sleepwalking, her animations
show a kind of off-balanced stance. I don't intend for Madotsuki to look as exaggeratedly off-balance, but it's interesting to consider all the same.
for an example of how Nayuki fights.
lastly,
http://www.gamefaqs.com/computer/doswin/file/580358/52629 is a guide to the game, in case you want to play through and see what things are like or see what other things there are in the game.
Sorry about how long this was, I wasn't sure if I'm supposed to make a new thread or something so I didn't. Also sorry for totally nerding out there at the end, I couldn't help it... and even if you don't use this idea the references might be useful for something else.