Hey I've reached the end game about a month ago and now I have basically everything on farm, but there's some things (mostly talismans) I haven't figured out how/where to farm.
I've read through a lot of forum threads and haven't found anything about what concerns me, so I thought I'd share some of my experience and thoughts.

Keep in mind that these spots have been chosen mostly based on usefulness of the items dropped, Sands of Time cost and real-time required to farm on auto.
Gold is not a factor as I like most of the end-game players am sitting on a few million and have nothing to do with it.

Here's a bit of info on what and where I farm and have had the most success:

3* Rainbow Evolution Runes - Underworld (Madness), Road to Ruin/Snake Eyes. The chance is about 10%. I've tried farming Game of Death and Number of the Beast, but the only change is the time needed to complete the mission.
3* Rainbow Evolution Shards - Rift Dungeons (VII-X), whichever you feel most comfortable with. I haven't got statistics on whether or not the chance is different, but I guarantee they drop on these difficulties.
Rare Souls - Rift Dungeons (IX-X), not sure about the drop rate on lower levels but I've gotten a few drops on IX an X (can't give you a percentage).

Void Talisman - Underworld (Madness) doesn't matter which level.
Thief Talisman - Haven't gotten a single drop of this in about 80 runs of Powerslave (Madness). Anyone got a good spot to farm this?
Burning Talisman - Haven't gotten a single drop of this after I finished the storyline. Anyone got a good spot to farm this?
Piercing Talisman - Rare, but drops on the Battlefield. I usually farm Point of no Return or A Matter of Life and Death.
Shock Talisman - Haven't gotten a single drop of this after I finished the storyline. Anyone got a good spot to farm this?
Vampire Talisman - Got only 3 ONCE from the secret mission on Underworld (don't remember which difficulty). Anyone got a good spot to farm this?

These are basically all of the *rare* drops that concern me. Does anyone know a good farming spot for those I haven't been able to figure out?