By luck, I found a solo knight game that I played in 2004. The level 67 solo knight earned 3,605,811 experience points. However, his dead partners who had never done anything still get some experience points - Warrior Mage 951229; Archmages 943304; Priest 940310). I guess it is a strong proof that:
1. Experience points can be earned not via killing monsters but just through completing quest by one of the party members.
2. Even dead characters can earn experience points through quest but the point they earn will be influenced by their background - That is why dead characters get different experience points even though they were all dead since the first minutes.
