Which Russian set of cards contains the most cards overall?
Russian refers to language = 'Russian'; contains the most cards overall refers to MAX(baseSetSize)
SELECT T1.id FROM sets AS T1 INNER JOIN set_translations AS T2 ON T1.code = T2.setCode WHERE T2.language = 'Russian' GROUP BY T1.baseSetSize ORDER BY COUNT(T1.id) DESC LIMIT 1