Lair and Haze V's Bullet witch and Vampire Rain

[Mummelmann]

Ooh, toughie. But, based on hype, I'd have to say Lair. Vampire Rain is an even worse game, but it was never totued as a massive blockbusting AAA title either.
Haze and Bullet Witch, I really don't know about those, never tried them. Probably never will either.