Complex sentence: Tommy Eriksson (real name Tommie Eriksson), in symphonic metal band Therion as guitarist 1995, drummer 1996-1997, guitarist 1997-1998 (on Vovin and Crowning of Atlantis).
Split into simpler sentences: Tommy Eriksson (real name Tommie Eriksson), is a musician who played in the symphonic metal band Therion. Eriksson was guitarist in 1995, drummer from 1996--1997, and guitarist from 1997--1998 (on Vovin and Crowning of Atlantis).