Lord Enma spawns a few seconds into the battle, followed by Ginger Snache, Ecto Doge, Ecto Snache, Ecto Baa Baa. The peons' spawn rates are proportional to their strength, with Ecto Doge spawning every 6.7~13.3 seconds and Ginger Snache spawning every 16.7~33.3 seconds. All four peons respawn infinitely.
After 30 seconds, Zoge, Znache, Zigge and Leggsy will spawn with 10 seconds between them. Each Zombie peon continues to spawn throughout the battle, and once again, their spawn rates are proportional to their strength, with Zoge spawning every 13.3~20 seconds and Zigge spawning every 40~46.7 seconds. Up to 7 Zoges, 5 Znaches and 3 Zigges can be seen in total.
Similar to Realm of Carnage, I used cat combos Seasons of Love, Lion King, and Three Kings, along with both Island Cats. The other cats weren't used necessarily, but were just in case. Rusher or Long Distance units would be helpful to chip down the base when Leggsy spawns.
Battle: Just spam both Islands until Lord Emna dies. Then Spam the rest of your damaging units, and use the cat cannon if necessary. The plan is to, if your Islands are high enough level, to kill Lord Emna quickly and attack the base before Leggsy spawns. Then Leggsy should spawn behind the base and, with enough damage, beat the stage before your units start to attack it.