A Sul'Dal bladefury, a Sul'Dal infiltrator and other related skeletal mobs found in The Sinking Sands are reported to drop the Bone Tablet at a "quick" rate. sun-baked skeletons ( -510, -153, -1348 ) Copy/waypoint -510, -153, -1348are also reported to drop the Tablets pretty regularly. The Unliving Trooper types just SE of the skeletons also drop the tablets. I found the drop rate at level 90 to be abysmal, it took me over 5 hours to get all I needed. Mummies also drop the tablets. Since the addition of quest icons beside npc names, you can now see which ones might drop it if you currently have no other quests with that type of mob.
The drop rate has improved and Sentinels of Anuk also drop the tablets.
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