Because XP is gained at higher rate than Spirit, and spirit is required for skills, there is a tendency for skills to fall behind the player level. Optionally, for Efficient leveling, player Genies use player XP to level, freeing up more spirit for skills. Spending a great deal of XP on genies, to max their skills, is best done just before level 40; the number of quests is very large and a lot of the quests cannot be completed after level 40. Or, late in a player's career, they will have huge amounts of XP to spend or can spend cash money to buy genies from other players.