Quick answer — Takashi Watanabe worked on A Certain Scientific Railgun S (Assistance), A Certain Scientific Railgun (Assistance), Toaru Kagaku no Railgun: Misaka-san wa Ima Chuumoku no Mato Desukara (Assistance) and 2 more anime.
Takashi Watanabe worked on A Certain Scientific Railgun S (Assistance), A Certain Scientific Railgun (Assistance), Toaru Kagaku no Railgun: Misaka-san wa Ima Chuumoku no Mato Desukara (Assistance), Boogiepop and Others (Assistance), Kino no Tabi: Nanika wo Suru Tame ni -life goes on.- (Music Producer).
