One Li'l Macho Legs Cat will be spawned after 20 seconds, up to 3 or 4 at first then a short pause (~30 secs), then they spawn normally again.
Those Guys and Crocos will also spawn, but not regularly.
Znaches can be seen if the player takes over 4 minutes to beat the stage.
Strategies
Strategy 1: Flight of the Bahamut
All you need is Awakened Bahamut Cat and Holy Valkyrie at level 30. All you need to do is release Bahamut and the Valkyrie... if they can't OHKO the Li'l Macho Legs Cats, they will knock them far enough back to attack again. Odds of defeat are virtually zero, be careful and adjust as needed. You should also bring some other units to destroy the enemy base quickly.
Strategy 2: A. Bahamut Solo
In version 6.0, PONOS added the multi-hit ability, which increased Awakened Bahamut Cat's attack power. But all you need to do is bring the Cool Japan Combo, then spawn Bahamut and win the stage. No need for Capsule Cat or Paris Cat unless you don't have the cats required for Cool Japan or Punchpunchpunch!.
Some important notes
Awakened Bahamut Cat may stutter due to the Crocos, this won't matter.
Firing a completely maxed Cat Cannon can actually do enough damage for Awakened Bahamut Cat to finish them off in 2 shots by himself.
The Cool Japan Cat Combo requires Samurai Cat, Sushi Cat, Sumo Cat, and Ninja Cat. To optimize Cool Japan, do the "Cool Ninja" (Cool Japan + Enter The Ninja) Combo, which involves adding Hayabusa and gives a Medium Speed boost, or the "Cool Bento" (Cool Japan + Bento Special) where you add the Sashimi Cat to give you +500 money at the beginning of the level.
Using Capsule Cat is very risky, because if the timing is bad, Li'l Macho Legs Cats will hit the Capsule and cause a Shockwave that can hit Bahamut, making it possible to lose your Bahamut and, most likely, the level. This is only a minor problem as by now, really just Cool Japan + A. Bahamut is required.
Strategy 3: Cyborg Cat
Lineup: Cool Japan Cat Combo and a high-level Cyborg Cat (the author's was level 40+5). You can also use Bahamut Cat, True Valkyrie Cat and Drunken Master Cat.
Spam Cyborg Cat until you win. Fire the Cat Cannon when a Li'l Macho Legs Cat gets close to your line of Cyborg Cats. This is similar to the Crazed Gross strategy.