This video is the process of where I learned how to exploit this pain in the arse boss. This is the first time I was in the area and I noticed he was a total pain, stopping me from exploring the region and grabbing all its sweet stuff. After some experimenting, I noticed that along the map edges he would disappear, then I found a spot he would burrow/unburrow.
This is the video of me stuffing around until I found the perfect rhythm. If you want to do this yourself, just make sure not to have a shell hammer or anything, which stuffs with the timing too much. Otherwise you can easily just strong attack cycle him in that spot until he's dead, with only a little risk of the odd attack. This means you can beat him on first encountering him, instead of clearly later on in the game as actually intended.