Conversation so far:
What is Therion's Sitra Ahra?
Sitra Ahra is an album from Therion released on 17 September 2010.
How did Therion's album Sitra Ahra do?
How did Therion's tour do, following the release of Sitra Ahra?

Question: What is the most important fact in the article?
Self-contained rewrite: What is the most important fact about the band Therion?