Looking for the name of an old cartoon that had white-haired druid-like females

There are men who are restrained, and their mouths are being held open. An elderly man places a large egg on top of a ramp, and the lower end of the ramp is connected to the mouth of one of the restrained men. The egg eventually hatches, and a big snail emerges from it. The snail then slowly slides down the ramp and enters the mouth of the man, who is forced to swallow it. As a result, the man is immediately brainwashed and gains additional physical powers and will serve as an additional soldier for that old man.