>>95989936
Creating a good boss can take some effort, but this method should be used sparingly, usually for the final boss of a series, because of how intense things get.

>Action parity
The boss has a turn before each player character. During this, they have their own actions and reactions, which can only be used against the player whose turn it is next. It's like monster hunter, where the monster is constantly swapping its attention between hunters and giving everyone an equal fight. Optionally, the boss can have a nova attack or chip attack at the end, a low-damage attack that strikes everyone for low damage (that you can react against if you have a reaction) to keep pressure on everyone. This prevents the players from exploiting action economy to drown the boss in attacks, because no matter how many attacks there are, the boss will always get to react. In turn, you don't usually need to put in secondary methods of defense like shields or FNP, or if you do, it should be low-intensity.