Let's see this achievemet http://ptr.wowhead.com/achievement=5866 first
After you complete both Druids and Wardens requests (300 marks) , three NPC spawns and preparing to sell you some nice stuff -
Oh, wait - you can't buy any those items yet until you give each NPC 125 marks
Calling the Ancients unlocks : http://i.imgur.com/T4wQX.jpg
Additional Armaments unlocks : http://i.imgur.com/Frbeb.jpg
Filling the Moonwell http unlocks : http://i.imgur.com/VbOqy.jpg
But there's still a good news, you can buy all these goods in cash, not marks.