Mist Barrier and Mystlock Lock Barrier.
They are related, yet there are differences between them.
The Mist Barrier is a type of ritual spell that lasts for a period of time and weakens as time passes. However, compared to a common spell, it lasts quite a bit longer, with the simplest seventh-tier Mist Barrier lasting up to three years.
The Mystlock Lock Barrier is the permanent version of the Mist Barrier. For the same version, its ability is somewhat stronger than the latter, but the cost is much higher, at least ten times that of the latter.
The cost for a seventh-tier Mist Barrier is around thirty thousand, including the Mage's hiring fee.
A seventh-tier Mystlock Lock Barrier costs between two hundred fifty to three hundred thousand.
The reason for the steep increase in the cost is not just the larger amount of materials required, but mainly due to the surge in the Mage hiring fees.