Efrain Rivera Castillo was born in 1925, Mayaguez (Puerto Rico), and died 12 March 1978, Manhattan. New York City, USA. Band leader, singer, composer, multi-instrumentalist Rivera was a pioneer of the trombone front-line in Latin music; some say he was the pioneer, whereas others maintain that Eddie Palmieri was the originator. Al Santiago, Alegre Records’ founder, is the one who deserves the credit. The all trombone sound was influential on Willie Colon, as well as other band leaders, and is often referred to as the emblem of urban salsa. Rivera was also known as “El Rey del Trabalengua” (The Tongue Twister Kings) because ‘… he would entertain fans with his improvised quips. His clear enunciation and alliterations, conjured up at lightning speed and perfectly woven in the timings and circumstances of music’ (quote taken from Aurora Flores 1978). Rivera was closely connected to the bomba and plena forms of his birth island. Ramon Rivera Alers was Rivera’s father and wrote many plenas. Rivera started his professional career when he was 16 years old, joining the William Manzano band. Rivera was also a professional baseball pitcher and played for Los Indios in Mayaguez from 1943 to 1945. He moved to the USA in the 1950s with Hector Pellot’s band, which was later commanded by Moncho Lena. He formed his own band, with the famous trombone front-line, after Lena’s disbandment. Que Gente Averigua was his debut album on Alegre Records. It featured the delightful instrumental “Lluvia Con Nieve” (Rain With Snow), composed by Mon. The album did not include any musician credits, but Al Santiago, the producer of the album, said that a stellar lineup had been assembled for the recording. They included Charlie Palmieri (piano), Eddie Palmieri, Barry Rogers and Mark Weinstein (trombones). Rivera’s self-penned song ‘Karacatis-Ki,’ a plena-dengue, was a huge hit. It was also the title track for his first Ansonia Records volume. Rivera’s 1975 collaboration, There Goes The Neighborhood/Se Chavo El Vecindario with Willie Colon helped him connect with the younger Latino audience. He also arranged the hit song, the plena “Ya Llego”. The session featured an impressive lineup, which included Jose Rodrigues (piano), Lewis Kahn (trombones), Jose Rodrigues(piano), Kako [timbales and conga], Ruben Blades (chorus) and Papo Lucca (“piano”), as well as Jose Rodrigues (trombones), Jose Rodrigues (piano), Kako [timbales and conga], Ruben Blades (timbales and conga) and Hector Lavoe (16). “Mon” was not immortal, and succumbed to the vices that life has to offer. He realized this and began to struggle to get rid of the “monkey” that had sucked his lifeline. Aurora Flores wrote in an oblique way about Latin artists. On 12 March 1978, he died from a heart attack at his Manhattan home. Johnny Pacheco produced the posthumously released Forever. Rivera sang lead vocals, arranged chores with Colon Agosto and composed one song. Allmusic