As far as i know its never did anything for casters... but on this server i was told protect actually helps casters? i was looking in the patch notes i even searched and didn't find anything.... so i thought i would ask here
"Protect is an ability given to some Melee classes and are used to protect classes that cast spells, when the protected class uses a spell [works on melee classes the same way of course] their aggro is lessened and some of it is transferred to the protecting player. This ability is only useful in PvE verses NPCs. [Works against realm guards etc. also, so simply just use it everytime you play in a group. Best bet while playing rvr is to put it on supporters or maybe the (pb)ae class] https://camelotherald.fandom.com/wiki/Protect