Weapons Can Win You Battles, Knowledge - Wars | Mission 4: The Doom That Came to Konos - side quests Heroes VI - Shades of Darkness Guide

Objective: visit 3 secret libraries and close the gate to Sheogh

Reward: 30000 EXP, +5 Magic Power, +3 destination

This mission is available right after completing "Demons at the Gate". You need to visit three secret libraries found nearby the enemy cities. The best method of completing this mission is quickly rushing to the library and afterwards using the Improved Town Portal to get away back to your town. If the enemy heroes are afraid of your army and don't chase you, you don't have to use this method and head to the next spot. The libraries can be found at three locations (M1, 11) or (M2, 23). After visiting all three, you have to return to the gate (M1, 10) and close it once and for all.