Retro's game should be finished by the end of the year. That gives them a full three year development cycle. And then there ought to be a new Luigi's Mansion coming along, too. Rumors have been consistent about that one since 2015, though they've fallen off since the summer.
The Screamapillar is easily identified by its constant screaming—it even screams in its sleep. The Screamapillar is the favorite food of everything, is sexually attracted to fire, and needs constant reassurance or it will die.