I have read over several threads on player training and have come up with a system that may work.
1. An NPC teaches the 'Teaching' skill which is a job skill
2. The teacher can teach all the theoretical knowledge they have for skills up to their teaching level.
so a teacher with lvl 0 and theoretical in Teaching, lvl 5 in Sword Combat and lvl 3 with theoretical in Mining can teach Teaching, Sword Combat, and Mining for the theoretical of lvl 0.
Base stats like Strength and Agility have much higher levels than the others, perhaps for the base stats, the limit its five times the Teaching skill level. so a teaching level of 30 could to teach strength to its maximum of 150.
at Teaching lvl 10 with no theoretical they can teach the theoretical for all skills except those of lvl 10 and above.
3. When a player has the teaching skill, then the 'Train' action can only be used on them by a member of their group. This should prevent players from pestering trainers too much. right clicking shows the train icon to group members.
4. This brings up the training screen where the student selects the skill to learn, they select it and hit 'Purchase skill'
5. The trainer gets a message "Do you want to train <student name> for <level> in <skill name> ?" they can accept or decline.
6. Hopefully, the total cost in PP and tria for the skill will be deducted at once to save both parties from pressing 'purchase skill' and 'accept' all day. There may be a waiting bar that appears as is one was casting a spell to show the time needed to explain the theory.
7. The cost in pp and tria is the same as if it was taken by an NPC trainer. The pp cannot be avoided because its what students use to learn an the tria vanishes from the system to represent resources being used up. The student pays both costs, if the teacher wants more money for himself, he asks that money be given to him. If the teacher wants to elliviate the cost of training, he gives the student some money.
8. Teachers get practice points in Teaching for each time they teach a student all the theoretical for a level. Perhaps even a little experience because teachers also learn from their students. The amount would be about as much as digging for ore (perhaps its usually just a few xp like failing to get ore with the chance of getting more, like succeding).
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With trainers being more available, and the tria being used up, it would provide a sort of money sink perhaps a little more than there is already. Though it could cause quite a bit of powerleveling.
Another idea would be to have a quest to get a Teaching Book which must be put in the mind slot to allow a teacher to train. This could create a limit on the number of teachers available or perhaps limit the types of skills they can train. (i.e. Job Skills, Combat Skills, Various Skills, Basic stats, etc)
Does this system look viable?