Pacification: Ineffective on NPCs?

[HaelseMikiro]

Check all of the tooltips on your spells and skills. They are divided into 3 groups: Weaponskills , Spells, and Abilities.
Pacification will block weaponskills (things that cost TP to use)
Silence will block spells (things that cost MP )
Abilities cost neither TP nor MP, and will be unaffected by those debuffs. So things such as Fester, Lustrate, Brutal Swing, Bloodletter etc. will always be available barring all-encompassing debuffs such as Stone, Stun and Sleep.
Almost all abilities used by enemies are exactly that, abilities. Unless SE decides they want us to stop a specific ability as part of a combat mechanic, using Shield Swipe for the Pacification is primarily a PvP tool, while the TP savings are certainly worth noting in longer PvE encounters.

[Billzey]

The above is incorrect. Pacification will prevent all enemy abilities from firing (excluding spells of course). They can still charge their abilities, but the ability will not actually fire if pacification is still in effect. If pacification does wear off before the ability finishes charging, the ability will still fire.

Basically, it can be used to interrupt any non-spell ability.

[Ryans]

The above is incorrect. Pacification will prevent all enemy abilities from firing (excluding spells of course). They can still charge their abilities, but the ability will not actually fire if pacification is still in effect. If pacification does wear off before the ability finishes charging, the ability will still fire.

Basically, it can be used to interrupt any non-spell ability.

They can't start a charge up weapon skill under the effect of pacification, either. For instance, on the first boss in Brayflox Hardmode, if you use shield swipe a second before he starts charging up bomb toss, he will sit there doing nothing for 6 seconds and then charge bomb toss. I assume it's because he is hardwired to use it at a certain time.

[Roris]

Depends on how the game classifies the abilities, sometimes they might seem like spells but are really abilities and viceversa. Just like how the lamb's summoning in AK can't be silenced because it's an ability instead of a spell, probably works the same in PvP for SMN/SCH Summon abilities but I don't really PvP. That's also another thing, a bunch of extra ability effects are really focused towards PvP instead of PvE, like the reduced healing from Disease or Storm's Eye when very few enemies self heal.