When it comes these classes there can be only one (at a time, terms and conditions apply).

1. Demon Lord
2. Hero

1. Warrior
   1. Fighter - Standard Progression

1. Knight
   1. Defender - Standard Progression

1. Berserker
   1. Woad Raider - Standard Progression

1. Wizard
   1. Grand Wizard - Standard Progression
   2. <Element> Wizard - <Element> Progression
   3. Elemental Wizard - Elemental Progression

1. Sorcerer/Sorceress
   1. Grand Sorcerer/Sorceress - Standard Progression
   2. <Element> Sorcerer/Sorceress - <Element> Progression
   3. Elemental Sorcerer/Sorceress - Elemental Progression

1. Cleric
   1. Bishop - Standard Progression

1. Ranger
   1. Scout - Standard Progression

1. Rogue
   1. Thief - Standard Progression

These classes are available to any tier1 class that meets the appropriate requirements.

1. <Weapon> Master - Weapon Master Progression

The only requirement is that you must reach the appropriate level for the new tier (i.e. level 10 for a tier 2 class, level 25 for a tier 3 class)