ALL CASTER NPCs
 

I havent seen a thread in here or maybe i overlooked it but even if a player dodges around the corner or out of LOS that all caster mobs are still able to cast detrimental spells ( all other than heal thru walls )

not a bug, was in patch notes. If they start cast and you are in LoS the spell will hit when it lands unless you are out of range. If they are rooted and you aren't in LoS they won't be able to start casting on you.