Issued (inverted) with Endless shadow / John Brunner.
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Summary
The arsenal of miracles: Bran Magannon saved his people, but became an outcast when he fell in love with the queen of the enemy. She told him about fabled weapons which she wanted and he offered to find them for her.
Endless shadow: Over 40 worlds were connected by a bridge system overseen by Jorgen Thorkild. Two of these worlds were at the heart of a dangerous situation. Jorgen had to defuse the situation without losing his own sanity.