To cut straight to the point. Since this is a categorized as a nightmare dungeon, attempts are limited whilst it also costs plenty of materials to just summon him. While doing this high level challenge the boss itself is pretty doable, however being shoved into the circular arena storm is less appealing. This is mainly the problem with my character since I can even barely see the right spot to move towards due to a similar color floor while also seeing corpses and my minions running around.
If you intend to make challenges for endgame like this, make sure the mechanics are noticeable or give us the option to make these more visible. These two points together are plain bad game design and need to be revisited. Either remove the respawn limitation so you don’t get penalized, make boss mechanics more visible or just remove the storm all together and make the boss himself have more challenging moves.