I just wasted hours trying to drop Groble Sky Effigy from sky clan in act 4. Looks like normal monsters:
• Groble ~ Sky Clan Stormcaller
• Groble ~ Sky Clan Witchdoctor
Doesn’t drop this item, and the only hope is hero monster and there is the problem. In act 4 with normal sky clan monsters the only Groble hero is actualy from death clan and drops only Groble Death Effigy.
This will sound really silly, but the place to farm this is Act 1. In the Burrwitch Outskirts between the cave and where you find Ulgrim is a small path with a named groble that will always spawn there. He has lightning effects as part of his package and the sky clan loot table. He doesn’t always drop the effigy but does so a good portion of the time and its a fast run to him so trying to farm a decent* one isn’t that bad.
It drops normally for me, I have found quite a few. Sky Clan is common in the Pine Barrens and even at the lower parts of the Rotting Croplands. And yeah, there is an Unique Groble Shaman who can always be found, around the same place you can find the entrance to the Smuggler’s Basin.
But btw, Groble Heroes can spawn anywhere, they are not “attached” to any clan, even if their skills and drops are based on them. So you can run into any Groble Hero anywhere where there are Grobles.
I don’t think Death Clan Grobles exist anywhere outside the East Marsh’s eastern side. Tyrant’s Hold has Ember and Stone Clan only.