I heard a side spawns every 24 hours and the other one every 36 hours[/quote]
Close enough. Right side spawns every 24 hours. After 12 hours, if the right side isn't killed, left side spawns, with 24mil HP, compared to the right side which has 30mil HP. Also, left head spams seal. And for some reason, left head has a chance to just stop attacking completely... It's happened once, and I'm not sure why.