Isso definitivamente soa como um conto de Timothy Zahn chamado "The Shadows of Evening". Foi publicado no livro Cascade Point em 1987.
A história (e é igual a "Nem Sempre o strong", também em Cascade Point) é sobre um Guerreiro das Sombras chamado Turek. É definido em uma colônia humana que está preso em uma tecnologia pré-industrial, porque as Sombras são atraídas por qualquer tipo de tecnologia.
Os humanos não podem realmente ver os Shadows (embora os Warriors tenham truques para obter uma rápida pós-imagem deles), mas entrar em uma área com Shadows é descrito como
... it started as a vaguely uncomfortable feeling, a sort of exaggerated nervousness. But as..it increased, and Turek could feel sweat popping out as his skin began to creep uncontrollably. A feeling of nausea get steadily in the pit of his stomach; his heart was already pounding loudly. His eyes felt like they were being squeezed into his skull.
Para lutar contra as Sombras, Turek:
... set his teeth and focused his mind just so... For a moment he felt nothing but the sickness in his body. Then, abruptly, something seemed to click. And he was in union with the Shadow. The darkness came like a wave, threatening to overwhelm him, to drag him into some nameless place where light never pierced. With practiced ease he deflected the assault and launched his counterattack. Be destroyed! Scatter to the winds! It resisted his blow, and for an instant Turek seemed to hear something: like voices, but faint and wordless and inhuman. And then he felt the resistance break, and he was back in the jewelry shop. Clearly the Shadow still existed; he hadn't expected to destroy it completely with a single assault. But his body told him it had reached its limit, and he knew better than to push Shadow-contact past that point.
Turek conhece um homem chamado Javan e seus seguidores quando ele ouve que eles foram para o antigo navio (que trouxe os colonos para este planeta) que está cercado pela Sombra de 8 milhas de diâmetro. Turek acha que eles devem ser charlatães. Ele lança um desafio e eles voltam para a loja que Turek sabia que levaria dias para se livrar da Sombra. E a técnica de Javan funciona.
Javan walked forward, slowly, stoping at the end of the Shadow. For a moment he stood quietly, and Turek saw use what seemed to be a slight modification of the Shadow Warrior afterimage technique. He raised his right hand, open palm just touching the Shadow, and the faint murmuring of the crowd cut off into an expectant silence. Turek watched his closely, ever sense alert for whatever trickery he was about to use. -- And suddenly Javan blazed with light!
O único encontro destruiu a Shadow (e eliminou Turek).
Javan pede a Turek para perceber que o novo método foi melhor, seria bom para todos. Turek sabe disso, mas a história termina com ele saindo sozinho.
He'd given his entire life to battle...but now Javan had proved that the sacrifice hadn't been necessary, that an easier way was possible. And Turek had wasted his life for nothing.