Why Scholomance?

[cookcpu]

After a bit of research, I think I've found out which mob you're talking about : Risen Aberration. Indeed this one seems to be immune to all spells but holy spells. You might find some useful advices in the comments of the wowhead page I'm linking.

Thank you so much. Now I can use my fishing rod to kill them.

[Maxion]

Thank you so much. Now I can use my fishing rod to kill them.

Your normal caster weapon works just fine and does more dps than your fishing rod in most cases.
Though i suppose the rod saves repairs.

[cookcpu]

Your normal caster weapon works just fine and does more dps than your fishing rod in most cases.
Though i suppose the rod saves repairs.

Hmm....my caster weapon is a staff but it can't do much damage, then maybe the skill level for the staff is low too.