git gud? The unblockables are clearly indicated with a red flicker and often do not have the level of tracking a regular blockable has to compensate.
Agares the most recent boss has only 1 unblockable and he uses it to start and end the pillar phase and its an extremely slow moving wave that anyone can run away from.
you'll fall for ohkos the first time and then never again unless you aren't paying attention.