So hey, remember Trickster's secret entrance from Chapter 2? Hahah yeah... well guess what.

Ozwella taking the ghosts from Helene's control slowly is a reference to the "Frog in Boiling Water" analogy you're probably familiar with if you've ever seen An Inconvenient Truth. The frog doesn't notice the water is slowly heating up, just as Helene didn't notice when her power was getting bled one ghost at a time.