Plague of Ba'lah is the 22nd expansion, launched on 5 of december, 2012. Announced as a faction that would take a look at the split races, as well as keeping with the development of the lore related to Ba'lah.
"The evil uncovered beneath the Jakei monastery in Broken Shard is spreading, seeding corruption and disaster throughout Poxanthuru. Change follows in its wake, from without and from within, and those who could stand against it are few."
As announced, after several expansions, new champions for the split races are released. This constitutes the exotic champions for each faction, as well as different split runes to fill the remaining four exotics slots.
In their moment, there was a webcast to preview and answer the questions related to this new expansion. It can be see here
After some months, it was announced the launch of a "Special Exotic Set". Similar to the midterms, originally it was intended to be available only through drafts, so the players would pay 4 tickets to enter in a draft, where they would get the chance to receive an exotic rune from the special exotic set. This would last a week, and then the new exotics would be available as usual on the marketplace. Unfortunately, the draft is bugged, freezing and making impossible for the players to pick their intended runes. The drafts were disabled, and the special exotic set is put to sale as any other regular pack.