Boss have crit damage as well?

Just so I can always survive from Dominus' attack (those fire from his hands) for 3-4 secs. But did a quick run on the weekend. I dead 2 times in a row as I cant survive for more than 1 sec from his attack. Is that mean his crit damage is on as he seem to have dealing more damage than before.

sure bosses can crit too just as you can and for projectile attacks (the white stream of ghostfigures he shoots) crit is rolled for the entire attack so either all crit or none during this attack phase of his