Stragedy 1 - Salon Cat and Valkyrie Cat
For beat this level, use Salon Cat or her evolved form, Paris Cat. Spam much as you can, along with meatshields. When the base is around 50000-60000 health, St. Pigge will come with the boss, Gory Groom will come.
When Gory Broom and St. Pigge comes, spawn a Valkyrie Cat. Also, you must increase the meatshields, cause Gory Groom can kill True Valkyrie/Holy Valkyrie/Valkyrie Cat and Salon/Paris Cat easily.