Finnish has 16, Estonian 14. Though most inflections can be derived via suffixes from about 4 of them (3 singular, 1 plural), What's probably complicated is when to use the correct form.
Axel Rudi Pell - guitars Charlie Huhn - vocals Jörg Michael - drums Volker Krawczak - bass Jörg Deisinger - bass Thomas Bodo Smuczynski - bass George Hahn - keyboards Rüdiger König - keyboards