"The Trial Cards are divided into three levels, namely low, middle and high. The low-level Trial Cards can only be paid with the energy of low-level ores. The mid-level cards can be paid with low-level and mid-level ores. The high-level ones can be paid with ores of all levels. The energy points can be exchanged. One mid-level equals five low-level energy points, and so on. To study in the Trial Tower, you need to pay five energy points to enter the low floors, where you can stay for three days. The mid floors cost five energy points too, and you can stay for four days. The high floors cost the same, but you can stay for five days."
As the teacher introduced, the students all mumbled and wrote them down. Yun Feng looked at the trial card in her hand, which only contained thirty points. If she didn't do anything, she could only study for thirty days, which wasn't nearly enough even for a low-level mage to upgrade by one level.
