You will have noticed that we only really have three playable groups more or less. If you are wondering about the Monster grouping please read Free Monsters
. Please post your monster here with the information.
For mortals well, they can have their own things going on at the same time right? And as far as demigods, please note that satyrs are undercover in many schools and sniffing out halfbloods. Its only when they think the demigods are in real trouble do they start herding them towards camp halfblood. Not all satyrs are the students as seen with Couch Hedge.
We also have the hunters of Artemis. Please note that not all the huntresses are demigods. Some could have been mortals that caught Artemis' attention and blessed with Immortality to join the hunt. While immortal they CAN die. They can be killed in battle.
As far as satyrs and others are concerned, if there is a big interest in them to play them then we might add another playable group.