Imperator Sael will appear as peons after Camelle appears.
Bringing cats that can take multiple hits/outrange Camelle are necessary here. Bringing Macho Legs cat might also help take down the Imperator Saels
One decent strategy is as follows:
Start off spawning 1-3 Crazed Whales, as they will do very well against the seals. The seals' deaths will give you the money for worker upgrades and Li'l Nyandam. Then rush with everything when you have enough, and the win shall be yours.
This stage becomes MUCH easier if you have the Chapter 3 alien treasures, since this stage was designed around having only 1 and 2 at this point.