It was Dentone's custom to retain the services of a figurist, in order to model his statues, prepare his chiaroscuri, figures of boys, and sometimes even animals and flowers, with all which he ornamented, not always with discreetness, his architectural views. The most erudite among the young artists here vied in offers of their services, desirous of profiting by the same art, and acquiring reputation. In the hall of the Conti Malvasia, at Trebbio, he was assisted by Brizio, Francesco and Antonio Caracci, and Valesio; also by Massari, in the grand chapel of S. Domenico, who attended him as well in the library of the fathers of S. Martino, where he painted the celebrated Dispute of S. Cirillo. In the Tanara palace he even engaged Guercino, who there exhibited his grand Hercules; while elsewhere he was assisted by Campana, Galanino, and Spada, and a few cartoons were afforded him by Guido himself. But his most useful colleague was Angiol Michele Colonna, who arriving at an early age from Como, and having studied some time under Ferrantini, finally united himself with Dentone, and became celebrated throughout Europe. This artist, according to Crespi, enjoyed the reputation of the greatest fresco painter of whom Bologna could boast; such was his spirited drawing both of men and animals, such his eminence in perspective, and every species of ornamental work, that he was himself alone equal to any grand undertaking, and painted alone an entire chamber at the Florentine court, and a chapel at S. Alessandro, in Parma. The perspectives in the tribune of that church were by his hand; the figures by Tiarini; and in several other places the perspectives were by Dentone, the figures by Colonna. It formed his peculiar talent, with whatever painter he might engage, so to adapt himself to the style and spirit of his colleague, that the entire work seemed the idea of the same mind, the product of a single hand. Nor did he require any delay; for whilst his companion proceeded with his own portion, he, with wonderful velocity, consistency, and admirable harmony, despatched the work; a gift for which he was very generally sought after, and more particularly by Dentone, who retained him after his return from Rome, until the period of his decease.