Experience - a measure of how much you have learnt from your mistakes. When talked about, it is often abbreviated to exp or XP. Heroes gain experience points mostly by defeating Monsters although there is a plethora of other ways too. When heroes gain enough experience points, their Level increases and they become more powerful and battle-hardened.
To see how much more experience you need to level up, look on the pantheon of might and find out the total experience (in the last column) which is the highest without being in the next level band.
Types of experience
Experience comes in two main forms, starite and monstite. Starite is the rawest form of experience, when it is freshly mined from the "Caves of Leveler". It is purple in colour and in this state it is useless to any hero. However, it has a distinct flavour which most monsters would (and do, usually) kill for. Once it has been digested by a monster, it transforms into monstite which is a fine golden dust which stays inside the monster. It is also very useful to heroes but must be earned by killing monsters to release it from them. Greedier monsters (usually fatter ones) provide the most experience because they are most likely to have eaten more starite. More powerful ones also have a lot since they have survived longer and so have ingested more of it.
Experience also rarely appears in questite and itemite forms too. Questite is the most unusual of experience because it is formed by the feeling of purest accomplishment that can only be obtained by completing a difficult task. Its colour and shape are specific to the hero, however many heroes say it smells slightly like peppermint. This is very high-level experience and gram for gram is worth ten times more than monstite.
Itemite is formed by magic inside special items. It is usually blue in colour and it's quality is unknown because it can either absorb or radiate experience. Heroes who encounter this should beware for this reason as it is very unpredictable.