In 1953, he was hired as the director of teaching affairs at Taipei Municipal Datong High School (臺北市立大同中學) and moved his family there.
He began to establish relationships with local artists, especially art teachers at the school, such as Chang Wan-chuan, Wu Dong-tsai (吳棟材, 1910–1981), and Chen Te-wang (陳德旺, 1910–1984).
[1][2] Tsai In-tang employed watercolor, oil painting, and sketching as his primary creative media, exploring both abstract and representational themes.
Throughout his artistic career, he continuously engaged in learning and observation, drawing inspiration from Western art movements such as Impressionism, Fauvism, and Cubism.
Scholar Lai Ming-chu (賴明珠) analyzed that in his later years, Tsai's style tended towards freedom, characterized by subjective use of color, flowing and unrestrained lines, vibrant hues, expressing the vitality of landscapes or figures.