Pigge appears as the boss. Players are advised to note that it has more health than Hippoe, making it harder. As Pigge is a Red enemy, using Axe Cat would make the level as easy as Japan.
For Chapter 1 - Start the battle by upgrading your Worker Cat. When enemies will come near your base, spawn your Tank Cats (you will need at least 3 of them out at all times). When Those Guys appear, use your Cat Cannon. Once you have upgraded your Worker Cat to max level you can spawn Gross Cat along with Axe Cats and meatshields. When Pigge appears, spam your Axe Cats and meathields.
Note - If you upgraded your Worker Cat at least once, then you could spawn your Cow Cat for extra support.
For Chapters 2 and 3 - Start the battle by upgrading your Worker Cat. When enemies will come near your castle, spawn your Wall Cats. Once you have upgraded your Worker Cat to max level you can start spamming your Axe Cats, Whale Cats and your meatshields.