Poisons in raids

[Athyest]

A buddy of mine told me that the only poison that works in raids is instant poison. I've been going through patch notes trying to see if this is true, but can't find any info on it. Can anyone confirm this? Thank you for any responses.

[Balake]

It's not true. Mobs that are immune to poisons are immune to all poisons instant or debuff. And mobs that are not immune to poison can be hit by any poisons. Rogues I know use deadly poison for bosses and instant for trash.

[Borefficz]

The main reason Instant Poison was used over Deadly Poison in Vanilla/Classic was a strict debuff limit which is not an issue here. Your only concern is not applying Deadly Poison to a mob that's supposed to be crowd controlled but other than that you're good to use it.