How to stop an Apostate Devil from Regenerating

[Jagerlord]

An Apostate Devil(Deimavigga) from Bestiary 5 has "regeneration 5"
The rules for Regeneration state "Certain attack forms, typically fire and acid, cause a creature’s regeneration to stop functioning on the round following the attack"
The Apostate devil does not list any type of damage to disable it. (It is immune to fire, and has Acid resistance of 10)

Compare this to the troll from Bestiary 1, which says "regeneration 5 (acid or fire)"

The rules also say "Creatures with regeneration heal damage at a fixed rate, as with fast healing, but they cannot die as long as their regeneration is still functioning"

This would imply that the Apostate Devil cannot be killed as long as its regeneration still functions, and there is no way to stop its regeneration from functioning.

Is this an error? Is there some unlisted way to prevent it from regenerating? Is it simply impossible to kill? Is there any other solution than locking it in a cage and casting forbiddance?

[Agodeshalf]

There have certainly been plenty of arguments around regeneration and ways to kill a creature that has the ability. A case can be made that ability damage which kills but doesn't do hit point damage can kill a creature with regeneration. Drowning, suffocation and/or starvation are also possible ways as well. In the case of trolls, I remember reading that starvation disables regeneration. Similarly death effects are another example of where people disagree. Some see that if the death effect doesn't do damage then regeneration doesn't help. Others point to the "can not die" phrasing in regeneration and say it is mostly a no-op. All in all there is just too much fuzziness in the language to make it clear and no clarification has been forthcoming no matter how long and heated the debates are.

[GM Rednal]

In the absence of other ways to bypass it, I'd rule that it's vulnerable to the default ways of bypassing Regeneration - which, in this case, means 11+ points of acid damage would suffice.

[VoodistMonk]

Just need to surpass the acid reduction and acid will still work. When in doubt, use more.

[Xenocrat]

Every other devil with regeneration has (good) as the means to overcome it. Use that.

[blahpers]

Nothing stops its regeneration ability, but you can still kill it using non-hit point damage, such as Constitution damage, suffocation, or one of the few non-damaging death effects.

[Pizza Lord]

Candle of Abaddon could do it. It turns off natural healing. Regeneration says it is like fast healing and fast healing says it is otherwise natural healing (magical regeneration or fast healing, like from regeneration or infernal healing would probably fall under the magical healing clause, requiring a DC 25 caster level check to work.) So you could either use it during the fight to keep it from healing (though it would probably avoid that area) or wait to drop it to unconsciousness and then light the candle and it dies.