As the level starts, Doge Darks will spawn. Gabriels will spawn after you when you attack the base. The Doge Dark spawn rate will increase for a while, when the Doge Dark spawn rate reverts to the beginning, and Gabriels will just stop spawning. These doges are extremely strong, so watch out. As the base gets damaged enough, a 150% Gentleman Bros. will come out with a Le'noir. Later, a second Le'noir will spawn.
Radiant Aphrodite and Super Galaxy Cosmo make this stage much easier, due to their high range and ability to hit the Le'noirs in the back. However, try not to let Super Galaxy Cosmo run into a Le'noir hit.
The battle becomes much easier when you take out the Le'noir. Be patient and you should eventually win.