Mário Álvares was a fine composer, an inventor of new instruments and a historic figure who was very influential for the generation of pioneers like Donga and João da Baiana. His songs were the vehicles for the apprenticeship of the instrument, by all of them, including Pixinguinha, who had Álvares as his cavaquinho teacher. He invented the five-string and the 14-string cavaquinhos (the "zebróide"). He was considered the best cavaquinho player of his time, soloing the melody and accompanying it with the harmony, at the same time. Highly regarded by Anacleto de Medeiros, he was regularly taken by him to the Bombers' quarters, where he used to give suggestions for Anacleto's orchestrations. In a famous meeting attended by Ernesto Nazareth, Catulo da Paixão Cearense, Quincas Laranjeiras, Donga, and other icons, Catulo defied Álvares to improvise over Nazareth's "Brejeiro," a new big hit then. After Mário's improv, Nazareth kissed him in the face, crying. Álvares had a big posthumous hit with one of his songs (with lyrics by Heitor Catumbi), in the Carnival. Among his compositions, can be mentioned "Feiticeira," "Na Aldeia," "Julieta," and "Entre Asas" (lyrics by Hermes Fontes).