Morgan Le Fay's planetary circuit
Circuit of planets established by Morgan Le Fay to keep anyone constructing an anti-Ori weapon free from attack. An Ancient transporter placed on each planet inside the circuit is capable of dialing the Stargate from a distance and transporting the confines of Merlin's laboratory to each world.
The space protecting the laboratory is identical, but the environment surrounding the Stargate on each planet may be entirely different. Only a handful of planets in the circuit have been charted, but it is likely they are numerous. The circuit itself is a sequence. Anyone caught inside of it is not transmitted to a random world, but a never-changing row of planets.
The Ancient transporter on Osric's planet is set to transport any non-Ori individual surrounding Merlin's cave to a desert world set in the middle of a great wasteland. Following this world is a frozen planet with ample volumes of falling snow, followed by a forested planet.
The Quest, Part 2 - SG-1 and Baal become caught inside Morgan's protective planetary circuit and must work together to break the cycle of dialing before the Ori can catch up to them.