Berserk is the third Crazed Cat Stage. It appears on the 9th of every month.
Note that the Crazed Axe Cat spawns at the beginning. It is highly recommended to bring a Rich Cat, a Sniper the Cat and Cat CPU to the battle. It should be noted that if you have more than two types of meatshields (Eraser Cat and Crazed Wall Cats), the main threat is the Shy Boy rush in the beginning of the game. These Shy Boys are the ones responsible for bringing down your defenses.
Replace King Dragon and Bahamut with ubers if you have any that outrange Crazed Axe and deliver relevant damage (if you only use stuff like Kubilan Pasalan, you will have no way of damaging the boss).
Just stall the boss for money at the beginning. When the Shy Boys come out, start spamming King Dragons and spawn Bahamut along with your meatshields, and whenever you feel the Shy Boys are too close from your cats, spam iCats (or any floating/red crowd control cat) and Paris Cats to push them back. The problem is, the boss has a longer range than Paris and iCat, so only use them when the Shy Boys are too close. Oh, and about the other enemies, they're weak enough so that they act as free money. If you have either Cameraman or Sanzo, they help a lot in plowing down the shy boys, especially if you don't have iCat.
Lineup: 3 Meatshields (preferably one 75¢ and two 150¢ cats), Sanzo Cat, Dread Pirate Catley, Cameraman Cat, Crazed Bahamut Cat, Ururun Cat, fill in the last 2 slots with whatever you like, especially Ubers which do extra damage to reds, or provide extra crowd control such as Peach Angels/Devils.
Start off the battle by killing the initial Sir Seal to earn some money (Thief Cat helps by doubling this money), and begin meatshielding when Crazed Axe cat arrives. He shouldn't push too fast due to his low damage, thus allowing you to build up even more cash. Not long after, the first Shy Boy will spawn, and here it is recommended to start spawning Sanzo cat and cameraman cats, they should quickly knock-back the Shy Boy, and prevent it from pushing to and destroying your base. As soon as you can deploy both C.Bahamut and Ururun cat, and start spamming everything except Catley, which you should only spawn if the Shy-Boys become a big problem and push. Once you stack more and more Cameramen and heavy hitters, the Shy-Boys should start dying faster and thus you will start pushing C.Axe away towards the enemy base. At this point you've basically won.
- Cheese Strategy: https://youtu.be/bkqFk4Tii7U