I love the idea of, one-shotting a pit fiend at range. Sadly, one either has to be invisible (err...really invisible) to study your target, or you have to study the fiend at a dinner party or something. Also, certain divinations can reveal who did it, yeah
Homebrew feats?
Grassy Knoll Death Attack
prereq: death attack special ability
function: add 30 ft to the range at which your death attack functions
special: you may take this feat multiple times. its effects stack.Fool the Gods Poison
injury, Will DC18, 1/rd for 10 rounds, cure 2 consecutive saves
effect: no damage, but if the target dies while under the effects, spells like commune will report the target died of natural causes.what do you think?
It seems broken to be able to assassinate someone from that far away. It might work as an epic level feat, but I still dont know if I would allow it to stack if I was the DM. I know casters can force saves, but they are limited to a number of spell. The assassin is only limited to a number of arrows. Another thing is that high level monsters have ridiculous fort and will saves. If you miss, or hit and it makes the save you have another issue altogether. You will also have to get your DM to approve the feats.
You can one shot the monster most likely, but it will take a good build. I would also suggest the splitting enhancement, and improved manyshot. IIRC each arrow should force a save. I dont know if that counts as one shot, but it is only one attack.