Doge and Squire Rel appear as peons before you attack the base, during the boss wave Mooth and Doge Dark appear as support, with The Face appearing as a Boss, 2 Shy Boys appear as a major threat during the boss wave.
Increase your money capacity by stalling the Doges in the beginning. Once you are completely maxed out, spawn in Bahamut and supporting cat units such as Dragon or Titan Cat. When the Shy Boys appear, rapidly spawn Macho and Wall Cat to stall them as your ranged attackers attack them. Once the Shy Boys are defeated, the level is pretty much done as the Mooths are relatively easy to kill along with The Face. Even with 2 and 3 star scaling you should have very little trouble with this stage.