The Knights Templar were tasked with protecting the greatest life-saving device of all Antiquity. 

 

They did such a good job that the Grail was lost even them. It is needed to rejuvenate the warriors of Sál Eldur.

 

Find the Grail, turn the tide.

 

Senses come and senses go, to find the Grail you must let sight go. Find the book that you can read minus the senses that let you see.