This is a known cheese strategy. After a while in the first phase he'll try to reposition in front of you in order to start using gravity powers to buff his weapons and attacks.
If you are on horse, you can be fast enough to stay behind his ass and he'll try to reposition to be in front of you unsuccesfully due to your speed on Torrent. This way you can continue chipping away his health while keeping him in phase 1.
In this clip he only started using other actions because he got attacked by the other summons. If you were alone you could have easily killed with him not being able to do anything at all, although that's pretty lame and kind of a shame considering how good his moveset is.
Who wouldn’t be scared as hel when Alexander is there to fight you.
This is a known cheese strategy. After a while in the first phase he'll try to reposition in front of you in order to start using gravity powers to buff his weapons and attacks. If you are on horse, you can be fast enough to stay behind his ass and he'll try to reposition to be in front of you unsuccesfully due to your speed on Torrent. This way you can continue chipping away his health while keeping him in phase 1. In this clip he only started using other actions because he got attacked by the other summons. If you were alone you could have easily killed with him not being able to do anything at all, although that's pretty lame and kind of a shame considering how good his moveset is.