Base exp is calculated based on how long it is estimated that dungeon will take to complete. The prestige exp is then calculated from the base exp and your prestige level. More specifically, base exp is calculated from: 1. What floor you are on 2. How many rooms were on the direct path to the boss (larger dungeon size = more rooms) 3. How many bonus rooms your team entered 4. Your own combat level (F2p players with combat levels above 90 get reduced exp) Those four I am sure about, but I think it might also take into account the levels of monsters compared to your team's combat levels, or how many enemies you left behind. As the configuration of rooms and placement of enemies is randomly generated at the start of the dungeon, there is some random element to the value of the base exp you will get at the end. As long as you open as many doors as you can, this can't be helped. The exp you get is not affected by what you personally did in the dungeon. The exp you get is not completely random. As for Archsaddler, you are probably recieving less exp than your partner because you have a higher combat level.