Credits and Levels

From AmtWiki

If you wish to fight or participate in a battlegame, you must conform to one class for each game. A person may advance in level in a class after having the requisite credits and passing a class test administered by your class Guildmaster. Only one attendance credit may be given on a single day, although Kingdoms may award bonus credits according to their corpora. You must play the class you wish to gain credit in. If no class is played but fighting takes place, you may take a Warrior credit.

All classes gain new abilities and levels at the following rate:
Level Credits required
1st Less than 5 credits in that class
2nd At least 5 and less than 12 credits in that class
3rd At least 12 and less than 21 credits in that class
4th At least 21 and less than 34 credits in that class
5th At least 34 and less than 53 credits in that class
6th 53 or more credits in that class