inde animus Tyriis non iam sua castra, sed ultro hostilem servare fugam, ne forte Mycenas, contenti rediisse, petant: dat tessera signum excubiis, positaeque vices; dux Martis operti sorte Meges ultroque Lycus.
Hence the Tyrians are emboldened no more to keep watch for their own camp but rather for their enemys flight, should they perhaps seek Mycenae, content to return. The watchword gives sentries their sign and turns of duty are settled. The leaders of the covert  warfare are Meges, chosen by lot, and Lycus by his request.
final_alignments\Statius_Thebaid_Book10.json