Question: Russian Roulette is the which number studio album by German heavy metal band Accept, released in 1986, it would be the last Accept album to feature Udo Dirkschneider as lead vocalist, Dirkschneider is a German heavy metal singer? 
Sentence (from "Accept (band)"): Accept achieved commercial success with their fifth studio album "Balls to the Wall" (1983), which is the band's only album to be certified gold in the United States and Canada, and spawned their well-known hit "Balls to the Wall".
Relevant evidence: No