The mountain throne once more is freed! O! wandering folk, the summons heed! Come haste! Come haste! across the waste! The king of friend and kin has need.
Tonight the Lord of the Eagles was filled with curiosity to know what was afoot; so he summoned many other eagles to him, and they flew away from the mountains, and slowly circling ever round and round they came down, down, down towards the ring of the wolves and the meeting-place of the goblins.
Yet this would be perilous, if the goblins were in sufficient numbers to overrun the Mountain itself, and so attack them also from behind and above; but there was no time for make any other plan, or to summon any help.
There are no more uses of "summon" in the book.
Show samples from other sources
I was summoned to the principal’s office.
I summoned all my courage and walked into the room.