The level starts by spawning a highly magnified Scissoroo and a few Kroxos with Shibaliens. After attacking the base, a huge group of Scissoroos are spawned along with more alien peons. As the Alien Enemies are killed off, Shadow Boxer Ks, Doge Darks, and Gory Blacks are gradually able to spawn. Eventually, the Alien enemies get replaced by a massive horde of Black enemies.
Although there are some powerful Alien Enemies at the beginning, they can easily be stalled if you have all anti-unstarred Alien Treasures. Only bring dedicated anti-Alien Cats if they actually prove to be difficult, as you want all the firepower you can get for the Black Enemies.
The combined DPS of the Shadow Boxer Ks and Gory Blacks will rip through even the tankiest Cats. In fact, almost every heavy attacker will only get to kill a few of the Boxers/Gories before dying, especially slower ones like Crazed Bahamut Cat, Li'l Nyandam and Takeda Shingen. If you have to use one, choose a fast attacker such as Ururun Cat.
Since most heavy attackers are just wasted slots, focus on cheaper ones with Area Attack/Shockwaves and quick attack speed, like Paris Cat, Cameraman Cat, Figure Skating Cats, Ring Girl Cat, Polevaulter Cat, Crazed Sexy Legs Cat, Crazed UFO Cat (True Form recommended) and Drone Cat. Using a Cat CPU will allow you to spam them more easily.
If you have Bombercat, use him. As long as you can keep them alive, the Black enemies' threat level will be next to none once you have two Bombercats on the screen.
Try to lure the Scissoroos in front of the Cat Base so you can build up an army before facing the Black enemies.
You will be using only 3 meatshields to prevent the Cat Deploy Limit from becoming a problem and to leave more space for attackers, but if you use Gold Macho Cat you must keep in mind that summoning him and Mohawk Cat together means forcing them to stay stacked and act like they were just one meatshield, which is the same thing as having one less meatshield, and that may be enough to make you lose.
Battle: The first part is easy, all you need to do is spam meatshields to keep the Aliens at bay while you start stacking up some Polevaulters and Parises; if the enemies are pushing too much, make sure to protect your attackers, by adding an heavy hitter too, as well as getting all anti-unstarred Alien Treasures.
When the Blacks start coming, spam everything you have whenever you can. If you arrive at this part with many Polevaulters alive, they will likely keep the HP of the incoming enemies close to knockback point, allowing the other attackers to do their jobs and continuously knock the enemies back, preventing them to push too much on your defenses, otherwise you may lose ground and some attackers.
If you lose now, try to understand why. If the Blacks were taking a while to receive any knockback, it may be due to the lack of area DPS, solve the problem by adding attackers and NOT meatshields. If you can hold the position, but only barely, add a long ranged Uber Rare or improve the stamina in some way.
What should be happening is for the Blacks to be knocked back after taking out few meatshields or even before getting to close, they have a strong pushing force that makes extra meatshielding quite ineffective, so you must rely on damage delivered continuously to keep your lines safe, otherwise you have no chance.
Strategy 2 (up to 4 stars)
Lineup: 3 meatshields, Cyborg Cat (40 works best, but 30 works too, just requires a little more support), Bombercat, Crazed Bahamut Cat, Ururun Cat, Cameraman Cat and any other fast attacking Area Attackers (Crazed UFO Cat works for non-4-Star).
Note: Cyborg and Ururun are the only required attackers here. As long as you can deal with the initial Scissoroo rush, you may not need most of these cats. Stall as much as possible before hitting the base, upgrading your Worker Cat to around 6 or 7. Stop upgrading the Worker Cat once all the enemies die and don't spawn anything after they do.
When the enemy base is hit, let your attackers die and lure them to your base. Summon a few meatshields, then summon Ururun. After that, spam every Area Attacker you've got along with meatshields. The Scissoroos should not be able to reach the Cyborgs. If they do, something’s being done wrong. Eventually, once you reach around 5-10 Cyborgs, you should start pushing. Summon Bahamut when you can. Cyborg and meatshields should be top priority when money is low. Eventually, your stack will be so big that it pushes with minimal effort and kills the otters with ease. Don't worry about the Cat Deploy Limit. As long as you don’t hit it while the Dark Otters are on the field, no enemies will be able to reach your Cyborg stack before being knocked back.