There , the hosts of Mordor , led by the dreaded Witch - king of Angmar , have succeeded in breaking through the gates of Minas Tirith -- using a terrifying battering ram named Grond .
Only Gandalf is left sitting on his horse Shadowfax to oppose him .
There , the hosts of Mordor , led by the dreaded Witch - king of Angmar , have succeeded in breaking through the gates of Minas Tirith -- using a terrifying battering ram named Grond , and only Gandalf is left sitting on his horse Shadowfax to oppose him .