Overwrites Treasure Hunter II, does not overwrite Treasure Hunter II with Thief's Knife.
Upon attempting Bounty Shot with a Treasure Hunter III+ on you receive a chat message saying "<player> uses Bounty Shot. No effect on <target>."
The 'no effect' message does not definitively indicate Bounty Shot has reached maximum potency. For instance, it is possible to get a success message TH3, followed by a no effect, followed by a success TH6. It is also possible if working with a Thf to get something like fail, fail, TH6.
Chat log will show "<Player> uses Bounty Shot. Treasure hunter effectiveness increases to Level X." on a successful strike.
The animation shows signs of success/failure.
Upon failure the animation mimics that of Shadowbind. (A small void appears at the mob's feet)
This will always occur when the player receives the "no effect" message.
Upon success a golden gleam appears at the tip of the ranged weapon and again on the mob when the ammo hits it.
Does not guarantee item drop, further testing required to determine % increase.
Chance to increase Treasure Hunter effectiveness with successive use.