Haven't found topics about this so sharing here as well
Which boss drops what items:
https://www.reddit.com/r/TitanQuestAE/comments/10v28re/eternal_embers_boss_drop_info/

Hello,

I'm looking for someone experienced with modding TQ to either create or help with creation of a mod that would make a sound when dropping an MI item. Farming MI items (Stonebinder cuffs in particular) would be easier as you wouldn't have to wait for the monster to fully drop items. It is also quite common for me to find MIs during normal play while backtracking -  because I left the area before the item finished rolling on the ground.

I've looked through the game files:
I have found in the game resources that the sound record is called EMBERSLEGENDARYDROP.DBR (RECORDS/SOUNDS/SOUNDPACK).
It uses soundName1,Sounds\item\emberslegendarydrop.mp3,
So I have tried to find mentions of it and Game.dll seems to be the place where this gets injected ino the game as it is the only match that is not a reference to the resource. None of the other matches have reference to item class type (Legendary)
If anyone knows how to amend Game.dll to include this sound for items of 'Rare' quality (so monster infrequents) iti would most likely solve the issue

Another solution would be to take this mod: https://steamcommunity.com/sharedfiles/filedetails/?id=1783348088
And strip off additional stuff that's in it. It's a little bit less future-proof solution as the mod replaces dropSound3d for all MI rather than patching item type drop sounds, but it (presumably) works. Patching the game.dll would be better but I've no idea how to do that and if that would even work. That way you'd only have to re-patch the .dll once after the game is updated.
I would probably be able to make a "custommaps" mod replacing all dropSound3d anyway. Especially that I have a very nice example of how to do it, but I don't know how to make a bounce mod so I'm stuck.

Can someone please make such a mod to make MI emit loud sounds when dropping or help me solve the issues I faced?