Fazula's Improbable Chain is a Legendary belt that was implemented in patch 2.3.0 of Diablo III. It requires Character Level 30 to drop. Originally, it only dropped during Season Four, but since Season Four's end, it drops for normal characters as well. The unique affix adds extra kill stacks to Archon immediately upon cast for all purposes, which is, in fact, equal to 240-300% extra damage buff for the duration. This is especially important when facing single powerful foes, such as bosses. In Vyr's Amazing Arcana Set Dungeon, it makes reaching 100 stacks much easier.