On 3 November 1627, Ilow was elevated to the status of Reichsfreiherr. On 27 November 1627, Ilow was present at Ferdinand III's crowning as king of Bohemia, he used the occasion in order to showcase his new coat of arms which bore an imperial laurel wreath. In May 1628, he received the command of a 600-man cavalry regiment from Philipp Cratz von Scharfenstein. He spent the following years, recruiting troops for other generals. In September 1631, he fought at the Battle of Breitenfeld (1631). In the early days of October 1631, he briefly occupied Zittau in Saxony before retreating to Bohemia which at the time faced a Saxon invasion. Despite the fact that Wallenstein was removed from command, Ilow continued to solicit his advice, significantly improving their relations. On 8 April 1632, Ilow was promoted into Feldmarschall-Lieutenant. On 13 April, the emperor formalized Wallenstein's return to the position of supreme commander. In April 1632, Ilow fought in Upper Lusatia, by October he had secured Zittau, Löbau, and Görlitz. On 11 November, he helped relieve Broumov from a Saxon siege, spending the winter at Bohemia's northern frontier. In February 1633, he successfully stormed Reichenbach. On 4 June, he captured Nimptsch, which was completely destroyed by fire. Wallenstein employed Ilow as his personal envoy, delivering important messages to the emperor and his generals. On 19 October 1633, he was promoted to the rank of Generalfeldmarschall on Wallenstein's request, much to the dismay of more experienced commanders. He accompanied the Generalissimo in his pursuit of Hans Georg von Arnim-Boitzenburg in the vicinity of Forst, he was then sent back to Lusatia, recapturing Görlitz on 30 October, following a costly engagement. Bautzen fell soon afterwards, Ilow extorted its citizens compelling them to pay a large sum of money. In December, Ilow returned to Bohemia.