Government Watchdog is the seventh stage in Sub-chapter 26, Sea Polluter.
There's really not much from the start, just peons. However, after the base is attacked, a massive horde of Celeboodles and Mistress Celeboodles will spawn. While they are single-targeted, they can demolish your units without enough meatshields.
There are tons of Celeboodles here. You need to make sure to summon enough meatshields to keep them from attacking your attackers while getting enough attackers to kill them.
After enough fighting, the spawn rate slows down enough that you can slowly make your way to the base and eventually win the level.
Since the stage is almost entirely Celeboodles, money is not going to be a factor so feel free to use expensive, spammable cats such Cyborg Cat, Flying Cat, or Wheel Cat. Jiangshi is also a great meatshield here too since it is essentially 2 meatshield and its price will be overlooked here.