u/malgrin

I read a post somewhere about using bloodmarks to skip final boss phases. Unfortunately, I came up just a bit short on phase 1, too much poison and/or daggers. At that point, I focused on dodging the air bolts, even if it meant giving up on the channel for a bit. Took me awhile to get through all three, but I was patient, and on phase 2 he went down.

Highly recommend finding a soul harvester, most of my better runs involved at least one of those. You don't need 19 keys, but it doesn't hurt to open most of the chests in the 3rd forest. Even still, I left that for the boss at 2 minutes.