Oracle Head
while not particularly devote to any one deity, a bog witches’ allegiance, if any, is purely out of self interest.
The large majority will worship one of the countless tutelary deities of the region. Others will worship one of their coven’s fallen, yet powerful, matriarchs.
Worship is unique and varied amongst covens, the only common factor is the use of oracles. Oracle heads, regardless of preferred deity, are required for communication with the divine.

A barbaric and savage act to acquire, an oracle head is traditionally the severed head of a giant or troll. Though other smaller raced oracle heads have been noted they typically will consist of multiple heads acting in unison.  
These heads act as a conduit, channeling the divine from the misellaneous portals that pock the world to the netherworld.
These insidious instruments will spew a language so dark and putrid that if a bog witch were to act as channeler it will cause them to combust or melt under the great power of the word.

The larger and more difficult to obtain the more likely the god will respond favorably. It is a sign of respect, devotion and highest of offerings. This is why giants, trolls and other large raced beings are favored.
Dragon oracle heads are incredibly rare but it is said that there is one found in the inner sanctum of the Twin Temples.