Wiki - Halloween Talismans
Each character that completes the Journey to the Underworld 30 times will be rewarded with an Evil Incarnate Talisman. Those who complete 30 runs of the Four Horsemen of the Apocalypse quest will be rewarded with a Hallowed Effigy. Both are powerful items that goes into the talisman slot though, of the two, the Effigy is the more powerful.
The stats shown here are an example as they vary for each talisman. Also, they bind to a character when equipped so anyone wishing to sell or trade theirs will need to do so before equipping it.