Eth's -25% defense

[Crystalion]

Monsters can be tagged by: Conviction, Curses, Open Wounds, PMH, slow, chill, poison, flee (is there any difference between Terror and flee?), Battle Cry, Taunt, and possibly some others...

Stun, War Cry, Shock Wave, Rabies, Cloak of Shadows, Slow Missiles, Inner Sight, freezing, Holy Freeze, Conversion, Mind Blast and possibly some others... :D

(and it hardly seems fair to collapse "curses", does it? ;) )
(e.g. since you mentioned poison, I imagine "burning" is possible to apply, but I've not kept track of those skills)
(another esoteric example might be the messed up way Sanctuary works, or rather, doesn't work... but I don't know).

p.s. yes, there are some differences in application of Terror and hit-flee and Grim Ward and Howl, but the "tagged" part is all the same (monster ai change), afaik.

edit: telekinesis, Leap, psychic hammer, bash, mind blast, smite and charge all, iirc, attempt knockback, which, if successful, seems to interrupt the monster and put them into hit recovery... this would be one of my favorite "tags" even though it doesn't last very long, usually (so chain cast!)

p.s. on topic: Malice weapon runeword at -100 and Soul Drainer gloves at -50 to monster defense per successful hit are pretty cool, if you can apply enough of them to make a difference ('sin blade fury is a neat way to malice things)... this is sticky, aka a "tag"