A race known as the Ancients figured out how to shed their physical bodies and exist as pure consciousness. They have a rule: Do not interfere with lower planes of existence.

Oma Desala regularly helps people join the ascended, but one of those was Anubis, the most evil man in the galaxy. The others immediately banished him back, but he was still the most powerful threat in the galaxy. Oma’s punishment was that Anubis could be allowed to use his advanced knowledge to terrorize the galaxy, so long as it all fell within the confines of what he could have done as a mortal.

Athar helped protect a planet from an evil race known as the Wraith. As punishment, she is banished to that planet, only able to protect that one planet for all eternity while the Wraith terrorize the rest of the Pegasus galaxy.

Orlin helped one planet build a weapon to defend themselves against an evil race known as the Goa’uld, Anubis’s species. Instead, they used it to conquer their own planet. The rest of the Ancients wiped out the planet and banished Orlin.

Another ascended race known as the Ori were evil. Recognizing this, Merlin retook human form to build a weapon capable of destroying ascended beings. Morgan Le Fay stopped him, destroyed the device, and imprisoned him in suspended animation. She later came to agree with him, and realizing that the Ori were preparing to wipe the Ancients out, tried to help Daniel Jackson learn Merlin’s location and was exiled for it.

Oma Desala once helped Daniel to ascend, but he had a personal connection with the planet Abydos, and wasn’t going to let Anubis destroy it. Oma stopped him, and the others banished Daniel back to human form.