So, at the end of EA, Wyll wants to find Mizora, free her from the drow, and break his pact with her.
What do you think will happen in act 2?
I mean, Mizora was obviously lying, has no intention to break the pact and will try to trick him into keeping the pact as it is, probably offering him more power if we manage to free her.
The Magic Mirror scene suggests that Wyll is more interested in reversing the power dynamic between them than breaking his pact with her.