His musical career started when he was in bands like Lyijykomppania, Stray Toasters and Nattvindens Gråt with Sami Vänskä and Tuomas Holopainen (both from the then yet to be founded Nightwish) in the middle of the 1990s.

[1] When Nightwish released their 1998 album Oceanborn, Wilska was asked to do the male vocals on the tracks "Devil and the Deep Dark Ocean" and "The Pharaoh Sails to Orion".

After his appearance on Oceanborn, Wilska also performed on the song "10th Man Down" on Over the Hills and Far Away in 2001 and once again with "The Pharaoh Sails to Orion" on Nightwish's DVD From Wishes to Eternity.

During May 2002 Tapio was featured on the album track "Farewell" by Finnish-based doom metal band Rapture reciting lyrics for the song.

In late 2002, however, vocalist Jan "Katla" Jämsen left the band Finntroll because of a virus-based growth on his vocal cords.