Been farming all the various locations I found listed online but no luck. I want to make sure if im doing something wrong or maybe the info on reddit and other sites is simply out of date. I've been switching to multiple characters so farming will be more intresting but I only have the quest to hand over the item on one specific character atm. Could it possibly only drop if you are on the character with the quest? Because it doesn't mention that as a requirement... I farmed shultz, shrooms in pollys forest and faduses in loopy tree forest.

Its mentioned as being rare but it feels more like extremely rare.; like ogre rings drop way more often than this thing. Maybe that's a bad comparison but I dunno.

The most reliable source of information is the ingame loot tables tool that you can open from the ESC menu.

This item is indeed pretty rare, to get perspective I spent about 100 hours at Ronaros and got like 2 or 3 drops.

Farming for the potion piece, I have about 20 sitting in my Altinova Storage.  Sherekhan was the place that gave me the most, then again it was an annoying grind there for quite a while.

If you are in need of Specter's energy, you can get them from the nodes at SE and Odyllita. 

You can also get it from Black Spirit Dice game.

That's mass of pure magic.

Also people keep saying that thornwood is the best place for that. I don't know how legit they are though.

Thank you for all the information. I haven't played much in the last year or so and mostly afk activities... I had forgotten about the loot in the escape menu.

Oh indeed. I messed that up. My bad

In that case. We had Specter's energy "event" where it could drop from Dark Rift Bosses. I got like 7 out of them. 

Invest 100hrs in farming then you get 1 or 2