dnd 5e – What count as damage by an ammunition when using Arcane Shot in regards to poison?

I am currently building DnD-5e Arcane Archer (from Xanathar’s Guide to Everything) character and considering how beneficial it is to take the Poisoner feat (from Tasha’s Cauldron of Everything ).

In particular the relevant section of the feat reads: (TCoE:p80)

When a creature takes damage from the coated weapon or ammunition, that creature must succeed on a DC 14 Constitution saving throw or take 2d8 poison damage and become poisoned until the end of your next turn.

The rules on basic poison in Player’s Handbook are similar so this is not unique to the feat.

Arcane shot feature (XGtE:p28-30) allows you to either apply additional effects (which include damage) after you have hit the target normally or have them roll saving throw instead of making an attack roll in order to determine if you have hit them with the special arrow. I am interested which of the additional effects or rolls trigger the poison, because as they count as being caused by the ammuntion and which don’t because they count as a different source.

In particular I am interested if the poison triggers when:

  1. You hit an enemy with normal attack before triggering arcane shot option
  2. Enemy fails Seeking Arrow saving throw
  3. Enemy succeeds Seeking Arrow saving throw, but still takes damage from it (triggers poison saving throw with no chance to avoid it)
  4. Same as 2 for Piercing Arrow (allows triggering poison on multiple enemies in line)
  5. Same as 3 for Piercing Arrow
  6. Enemy is within range of Bursting Arrow effect (triggers poison in an area)
  7. Enemy moves after being hit by Grasping Arrow (allows triggering poison multiple times on one enemy)

So which of these effects trigger poison applied to an arrow, and which don’t?

My intuition says that 1-5 would, but 6-7 wouldn’t but I am not sure about it.


Note: I plan to add this character to my character backlog without any particular GM in mind, who would run the game, so “Ask your GM” won’t be helpful. It might even be the case that I myself will be the GM and either offer this character as a prebuild or NPC.