Hi Jeff, wasn't that you on the elevator in the first TTK mission? And if you are talking about the dreadnaught keys you need wormsinger runes to activate altars/totems that summon hive/taken champions that when killed drop wormfeeder runes which have a specific action(s) to be completed. When you charge it up by completing the task it turns into a random key that gives a hint to the location of the chest that it opens in its description. Hope this helped