Nalle Österman plays drums in Chaosbreed, the Finnish death metal supergroup consisting of bassist Oppu Laine (ex-Amorphis, Mannhai), guitarist Marko Tarvonen (Moonsorrow), guitarist Esa Holopainen (Amorphis), and vocalist Taneli Jarva (ex-Sentenced, The Black League).



Nalle Österman previously played in Gandalf. He is also known as sticksman with Sonic Roots, uding the moniker Björn Again Electric.



In June 2006 Nalle Österman temporarily replaced Mikko "Junior" Pietinen in Mannhai.