After 1930 a new change could be observed in the spirituality of the colony. Step by step an avant-garde artistic tendency promoting leftist ideas started to take over. It was obvious from the point of view of the younger generation that art should reflect the social reality and they were seeking for adequate methods to express these ideas. Very soon, a group working in the spirituality of expressionism, cubism and art deco was organized inside the colony. András Kunovits, who arrived here in 1931, must have been partly responsible for the appearance of these concepts. He was so firmly expressing his radical ideas that he soon found himself in the centre of the attention of the rebel group made up of Olivér Pittner, Sára Kahán, Lilla Csizér, László Matolay, Lídia Agricola, Márton Katz. Very soon more representatives of the young generation joined them and some of them decided to join even the illegal leftist party. As the nonpolitical attitude had been one of the basic principles of the colony, since Simon Hollósy's time, András Mikola had to expel some of these students from the school in 1932.
In consequence, the group of the young leftist painters decided to find a collective atelier for themselves. At the beginning they asked József Klein to be their mentor. The latter had been working in the circle of Picasso in Paris as well and was quite enthusiastic about the request of the young people who took an interest in avant-garde tendencies. He assimilated in his works the results of expressionism, constructivism, and neoclassicism: Landscape with Hills, Nudes. Besides his paintings, his activity as a graphic artist is worth to mention as well. He worked with drawings, watercolours, coloured linoleum engravings as well. He hired no models. His disciples were allowed to choose any theme they desired. They usually made a draft, which was technically analysed by Klein. Thanks to the huge library of Klein, his pupils could get acquainted with Bauhaus periodicals, the books of Lajos Kassák, the oeuvre of Frans Masereel, Käthe Kollowitz, George Grosz, Chagall, Picasso, Braque, Leger, Kandinszkij, Archipenko, which had a great role in the improvement of their own formal language. Gyula Derkovits, Béla Uitz, Sándor Bortnyik and African sculpture considerably influenced them. The group rejected l'art pour l'art and was seeking for a simplification of methods of expression, in order to convey strictly the essence of things.
In 1932, Sándor Ziffer took charge of the group. In this period he worked under the influence of German expressionism. His paintings were characterized by nuances of blue and green that were dissolving into each other. His works were well built, summarizing, decorative: Watermill, The Morgó Valley, Springtime at the Stream, Nagybánya Landscape, Banks of the Zazar at the Old Mill. He changed the methods of learning. They hired a model and he rectified the works of his students twice a week. He was very enthusiastic about the fact that the young people took an interest in avant-garde art, but he didn't share their political beliefs.
The young people were influenced of course by those progressive artists who spent some time at the colony without sharing its spirituality: Dávid Jándi: View of Nagybánya, Jenő Pászk, Vilmos Perlrott-Csaba: Banks of Zazar, János Kmetty: Street at Nagybánya, János Mattis Teutsch: In the Mine.