The mighty Zommoros has slightly increased the drop rate on Legendary precursor weapons from the Mystic Forge from both Rares and Exotics.
The drop rarity of Rare and Exotic weapons from certain places in the world (champions, veterans, and players in WvW) has been increased. Rares and Exotics should be much more likely to drop and every champion should be guaranteed to drop loot. This was to ensure that world loot drops were not a significantly worse way of acquiring rare and exotic items than crafting and running dungeons.
So, for those of us working events, its a good idea to kill those events that have champions and veterans since now they are more worth the effort. As for the Mystic forge, just remember the chance to get precursor items is still pretty low but is now only a little better.
