Once you've attained your first legend class, you can gain in a second realm lord class for 400 quest points. You will only receive half of that class's bonus, but all of the skills. Once you've gotten to level 30 in that class, you can also gain in one of its legend classes.
Living Shadow:    
  Dark Shadow (Dsh): Perfect stalking class, can become almost entirely invisible.
  Mystic Shadow (Msh): Controls powerful traps and mind-altering spells. Can also morph their body visually into different forms.
BladeMaster:

    
  Paragon (Par): Incredible defensive melee class. Can stop some circles and use shields more effectively.
  Tetrarch (Tet): Very good group leader, decreasing the group experience penalty. Can also block critical hits against party members. Can also improve stats on virtually all weapons.
Malakim:    
  Archaic (Arc): This class is a good spell damage reducing class. Also has a skill which allows the archaic to substantially increase HP and MP regeneration.
  Rejuvenil (Rej): This class can stop and prevent combat in most rooms. They can also cool burning items and speed themselves up in combat.
Exorcist:    
  Malevolent (Mal): Malevolents have the ability to control the most powerful charmed creatures on the mud, however, they can only control one at a time. They also get an additional damage-over-time spell.
  Lich (Lic): This is a great class for their cloak:lifetap -- it steals hitpoints from whoever you're fighting every round and gives them back to you. They also have an extremely powerful room-wide attack spell.
Deity:    
  Clergy (Clg): Clergy have a cloak which noticeably reduces all incoming damage. They also have a powerful group healing spell.
  Heathen (Hea): This class has an ability to reduce the effectiveness of enemy reflection and absorption cloaks. They also have a powerful group healing spell and a spell which can regenerate the user while in combat.
Dark Templar:    
  Dark Cistercian (Cis): Controls energy to make spells much more powerful. Can also slow enemy movements and cause hallucinations.
  Planergetic Odylicist (Pla): Control a variety of elemental spells and can surround themselves with a wintry cloak, changing their affects.