The final buff, Crowned by Dragons, comes from acquiring both of the previous buffs at the same time, and will let you damage the final boss: Akardon, The Pitiless Mind.
In the second encounter, you'll need to use this to defeat the Gatekeeper Wyvern's in each red area and then activate the node near to each to unlock the gate. This lets you travel into the red misted areas without taking continuous damage. In the first encounter, you'll want to examine the three symbols by the locked gate, then kill the phalanxes in that order, going top-to-bottom based on the symbol floating above each.
