An Oyarsa is a person (usually an angel) set to guard a world. The idea originally comes from C.S. Lewis's space trilogy. The plural of the word is 'Oyarsu'. In general, each oyarsa will have a primary ability in addition to nearly complete control of the world he was set to protect.
- Viritrilbia (Mercury): Focuses on knowledge and magic nullification.
- Perelandra (Venus): Focuses on healing.
- Thulcandra (Earth): Focuses on flaws.
- Malacandra (Mars): Focuses on battle strategy, particularly using another location as a source for an attack.
- Lurgandra (Saturn): Focuses on brute force. Lurgandra can multiply sheer power by a factor of ten.
- Glundandra (Jupiter): Focuses on administration. In addition to being the most powerful Oyarsa, Glundandra can coordinate the other Oyarsu.
- Nevrilbia (Uranus): Nevrilbia focuses on teamwork and can join any two beings into a single being with their combined power. Because this adds together knowledge, defense and offense, this always more than doubles their total power.
- Adenandra: Adenandra was the first Mortal Oyarsa, an experiment by Glundandra. The world he was set to protect was destroyed by a fireball and his name was shortened to Aden. Not having any particular place to protect has made him into a long-range strike fighter. Aden neglected to properly choose a focus and changes his modus operandi occasionally.
- Nilvarandra (Valiensa, setting of The Lost Tome): Nilvarandra is a mortal oyarsa. In The Lost Tome, a new Nilvarandra is ordained to replace a long-dead oyarsa. Nilvarandra focuses on food.
- Argusandra (Pluto): Argusandra was a self-declared mortal Oyarsa. A powerful mage, he remained ruler of Argusandra for only three days before being defeated by the combined skill of Viritrilbia and Perelandra.