the overview graphics with the level and kill requirements is pretty handy
The graphic is a little misleading.1. For "The Beast in the Ice" you need to do Tier 30+ NM Dungeons.2. For "Lord Zir" you can collect the mats from World Bosses OR Legion Events.3. For "Duriel, King of Maggots" you need to collect mats from "Echo of Vershan" AND "Grigoire, The Galvanic Saint".