The end of the game is broken up into three acts.
Act one is a chase, mirroring the rest of the game, the difference is that it is a chase downward.
Light at the end of the journey
Gosh Darn It!
This is probably the most horrific creature in the game; Ygsmyre, Keeper of the God Blood. Exoder and him have some history.
Quickly breaking these blocks while trying to outrun Ygsmyre is the big challenge here. If he catches up you're toast. You've also lost both staff and orb so you have no means of attack (or deflecting) but that won't mean much in this first act, outside of a few straggler enemies near the end of the chase. But wait! Certain blocks contain the minds of those who have fallen into the Adit, if you spot them and break the right blocks they will delay Ygsmyre's descent!
Alas, cornered.
All that progress, all that hard work, only to be smacked back down to the bottom.
Up next, Act two, Exoder strikes back!...sort of.