To start off the battle, the enemy base will spawn two Heavenly Hippoes and Zomboes. After a minute, Heavenly Hippoe and Zomboe will continue to spawn at a slow rate (every 26.7~40 seconds). There are also three Dagshunds; the first will come out after 40 seconds, while the other two each spawn 40~60 seconds after the last.
The stage plays out how you think it would. Ramen Cat can be used in the beginning to stall the Heavenly Hippoes, and Can-Can Cat and Castaway Cat serve as low-cost damage dealers. Zombie killers aren't even necessary since you can just spam meatshields and Can-Can Cats to win the level.