Is this game in any way scary? I'm so used to other Zelda games where it looks all nice and bright, I mean even twilight princess doesn't look as weird and twisted as this (in a good way).
That moon is straight from nightmares.
It's very eerie and unhinged, yes. Feels like a demented dream. But at the same time there's a consistent internal logic to the world and the way it works. It feels very grounded. Everything comes together like clockwork -- all the NPCs, their intersecting storylines, their branching paths, the events happening at the same time so you can't see everything in one 72-hour cycle. There's really nothing else quite like Majora's Mask, IMO.
Adding to the uniqueness are the transformation masks. Rolling around as a Goron reminds me of the podracers in Star Wars Episode One. Turns a trip around Termina Field into a demolition derby, complete with jumps. And the Zora controls like a jetfighter underwater. Seriously exhilarating, slicing the surf, drilling through enemies and leaping out of the waves like a dolphin. And the Deku Scrub can spin like the Tasmanian Devil, and has some neat moments where you have to fly from one flower pod to another.
The other masks enhance Link in various ways -- the Bunny Hood actually makes him run twice as fast, for example. Some are more situational, I.E. they yield a certain effect with certain characters, but they look plain cool to wear, like Gorman's Mask and its constant stream of tears.