Нађох нешто детаљнији опис уништења Гепида, који помиње кретање аварске војске кроз Моравска врата, међутим како се и усамом тексту наглашава то је било само тактичко кретање војске,а не миграција Авара. Ево тог текста:
In the critical days during the winter of 566–67, emissaries of the Langobard King Alboin met with Bayan somewhere between the Elbe and Oder rivers; Sigebert, Alboin's brother-in-law, had probably acted as mediator between the two powers. The envoys proposed a joint, two-front assault on the Gepids, as well as an 'eternal alliance' ('foedus perpetuum', which in Langobard usage signified a military alliance).[14] They accepted Bayan's demand that, in the event of victory, the Gepids' land, population, and riches be given to the Avars; they even evoked the tempting prospect that the Avars, if they captured Pannonia Sirmiensis, might easily cross the Sava River and realize their dream of occupying Scythia Minor and Thrace, or indeed press on all the way to Byzantium.
Few details of the famous joint operation survive, for the Langobards were more intent on recording their own achievements. {1-221.} It is likely that, in keeping with the terms of the agreement, the assault was launched by the Langobards. The Gepid King Kunimund drew together his forces 'from several directions'[15] to meet the Langobard attack. Only after he had taken this fateful step did he learn of a second, Avar attack (Tristis ad Cunimundum nuntius veniens, invasisse Avares). As a result of the strategy that had been agreed upon with Alboin ('ut cum Alboin statuerunt'), the Avar army (it must be emphasized that what happened was an attack by Avar forces, and not a 'migration' of the Avar people) was able to break through the sealed frontiers (terminos edicit).
Bayan's ultimate objective was Sirmium; at the original negotiations, he already requested that Langobards provide guides who could lead him against Sirmium. Moving in through the Moravian Pass and along the left bank of the Danube, 'taking immense pains and covering a long distance,' he set upon the Gepids. The late Langobard chronicles naturally attribute to their own king and people the glory of defeating the Gepids. But Byzantine contemporaries, who were well-informed and had a direct interest in the matter, recorded that it was Bayan who had 'defeated them in war' and 'smashed the Gepids' state'.[16] They were undoubtedly right; on this occasion, the Langobards had played but a secondary role and reaped the benefits of their allies' sweeping success.
Thus Bayan defeated the Gepids' main force, led by King Kunimund; the latter was killed in battle, and Bayan, in keeping with ancient Eastern custom, had his opponent's skull turned into a drinking bowl before presenting it — ostensibly in friendship — to Alboin. Thereupon, Bayan immediately crossed the Danube to attack Sirmium's Gepidic defenders. The commander of the latter, Usdibad, did not wait for the Avars to arrive; he and his soldiers surrendered to the East Roman forces, who were on a state of alert. The Gepids' heir apparent, Reptila, fled to Constantinople, as did the head of the Gepid Arian Church, Bishop Thrasarik. By the time Bayan reached Sirmium, the town was already defended by {1-222.} Bonos's Byzantine troops; the latter repulsed the Avar cavalry, which was unprepared for the siege of a fortress.
