Answer:Alexios I Komnenos ( Latinized Alexius I Comnenus, was Byzantine emperor from 1081 to 1118. Although he was not the founder of the Komnenian dynasty, it was during his reign that the Komnenos family came to full power. Inheriting a collapsing empire and faced with constant warfare during his reign against both the Seljuq Turks in Asia Minor and the Normans in the western Balkans, Alexios was able to curb the Byzantine decline and begin the military, financial, and territorial recovery known as the Komnenian restoration. The basis for this recovery were various reforms initiated by Alexios. His appeals to Western Europe for help against the Turks were also the catalyst that likely contributed to the convoking of the Crusades.
Explanation:
It was manly because of the catholic church which remained in the base of Rome. It drew pilgrims from all over Europe, educated clerics to read and write, support arts and architecture.
One method,if my understanding is correct, is to attack by surpirse or to kill as many people as possible.
By doing that, the killing of numerous/millions of people, usually end on on planes, buildings... That type of stuff.
They usually do bombing of large areas.
~Hope this helped :)