The boss, The Face, spawns at the very beginning of the stage.
30 seconds in, the first Cala Maria spawns.
~16 seconds later, 2 Brollows rush to your base.
~37 seconds after the Brollows spawn, the second Cala Maria spawns, soon followed by 4 Brollows ~3.3 seconds later.
~50 seconds after that, Brollows spawn infinitely at short intervals; 1-2 Brollows every 32.6 ~ 33.3 seconds.
Strategy 1 (Ubers and Collab units)
Deploy just enough Mohawks to keep The Face from advancing, and upgrade your Worker Cat to hold 7500¢. When Cala Maria appears, continuously meatshield with Mohawk and Kyubey, and spawn Cosmo when cash allows. Keep adding Cameramen when cash recovers, and Jiangshi when possible. Cosmo will clear most of the Brollows in time.
Once Cosmo pushes Cala Maria behind The Face, use Fishman Cat to hit The Face.
Do NOT use the Cat Cannon, or Cosmo may run up and get killed.