I think you mean "nerf." Your diction gets on my nerves... pun intended.
I don't think either is overpowered.
ice shield
procrastination
thorn shield
phase shield
hope
diamond shield
bone wall
fire shield
dissipation shield/field
fog shield
dusk shield
All of those effectively deal with both.
devourers
discords
earthquakes
black hole
destroy
explosion
steal
All of those effectively deal with both.
reverse time
plague
lightning
shock wave
fire bolt
rage potion
rain of fire
aflatoxin
ice bolt
drain life
antimatter
chaos seed
mutation
gravity pull
basilisk blood
freeze
thunderstorm
unstable gas
All of those effectively deal with shriekers.
maxwell's demon
fallen elf
purple nymph
virus
grey nymph
armagio
otyugh
auburn nymph
amber nymph
flying adrenalined staffs
red nymph
arctic squid
toadfish
blue nymph
eternity
scarab
pharaoh
parasite
black nymph
All of those effectively deal with shriekers.
Seems like a lot of options to me. If you didn't notice, most of them aren't in fire. Maybe you should try some of those.