Originally Posted by
SeraviEdalborez
The short version: if you can't block or parry it? It's probably magical. Magical attacks also will never proc Eye for an Eye, and crossclass Virus does nothing on these enemies except waste the Antibody timer for a SCH or SMN.
Stuff on a fight-to-fight basis
Coil
Everything a "node" type enemy does (ADS as an example) is magical. E4E does nothing, Foresight does nothing, etc
Ifrit
M: Nails exploding
P: Incinerate (confirmation needed, been forever since I've tanked this)
Titan
M: Tumult, Weight of the Land, bombs
P: Rock Buster, Mountain Buster, Landslide
Leviathan
M: Everything head does (including Tidal Roar), spumes exploding
P: Everything tail does