Earlier, the developer revealed it was forced to remove a 'creature with a hundred eyes' called Argus but unfortunately it was not the only boss to be cut. Here’s some of the interview with Asmussen held by Destructoid: (warning, here be spoilers)
"We had [Argus and] we had a massive cyclops. I don't know if you remember the door where you enter Hades' Palace; you burn the bramble that's in front of it, and you open the door there. We had a couple of cerberus there guarding the door. The original plan was, the first time you ran through Hades to get to that entrance, that's when the cerberus come down."
"The second time you come through, you just burn the bramble, and you would start to lift up the door, and [the cyclops'] hand was going to come underneath it and just whip it up. From the other side was going to be this huge cyclops, like twice as big as any cyclops you've ever seen before."
"We had a branching mini-game on him and everything. It was really cool, but him and Argus, to get them to completion would have meant that other things would have suffered, and they still had a way to go."