These are some examples that you can refer to to further understand how it works. EXAMPLE 1: Train attack from 5% to 25% for a troll. ============================================================================== Help on skill : Attack Guild Level : Alpha Skill type : Combat Base Experience Cost : 459 ============================================================================== This skill helps determine how often a player will hit the enemy in combat. It directly influences the damage that the player inflicts. You can not be an effective fighter without a lot of training in this skill. ============================================================================== Created By : Unknown ============================================================================== Troll: skill: 104%, spell: 160% (By: Evilpriest, Special thanks: Zicoo) 015: 2 2 020: 2 4 025: 1.75 7 Therefore, exp needed to train attack: (459 x 104% x 1) + (459 x 104% x 2) + (459 x 104% x 4) + (459 x 104% x 7) = 477.36 + 954.72 + 1909.44 + 3341.52 = 477 + 954 + 1909 + 3341 (round down) = 6681 Alternatively, it can be done by: [459 x 104% x 1] + [459 x 104% x (1 x 2)] + [459 x 104% x (1 x 2 x 2)] + [459 x 104% x (1 x 2 x 2 x 1.75)] = (459 x 104% x 1) + (459 x 104% x 2) + (459 x 104% x 4) + (459 x 104% x 7) = 477.36 + 954.72 + 1909.44 + 3341.52 = 477 + 954 + 1909 + 3341 (round down) = 6681 EXAMPLE 2: Study light from 5% to 25% for a troll. ============================================================================== Help on spell : Light Guild Level : Alpha Spell type : Special Sp Cost : 129 Casting time : 4 rounds Base Experience Cost : 277 ============================================================================== Use of this spell will illuminate a dark room. The power of this spell is based on the caster's level. ============================================================================== Created By : Unknown ============================================================================== Troll: skill: 104%, spell: 160% (By: Evilpriest, Special thanks: Zicoo) 015: 2 2 020: 2 4 025: 1.75 7 Therefore, exp needed to study light: (277 x 160% x 1) + (277 x 160% x 2) + (277 x 160% x 4) + (277 x 160% x 7) = 443.2 + 886.4 + 1772.8 + 3102.4 = 443 + 886 + 1772 + 3102 (round down) = 6203