Soul Accumulation

Soul Accumulation collects the soul energy needed to use for Soul Reaper's ability at constant interval. The initial soul energy amount is 5 maximum, The skill will no longer collect the soul energy when reach maximum amount.
 * [Level 1]: gain 1 soul energy per 60 seconds
 * [Level 2]: gain 1 soul energy per 50 seconds
 * [Level 3]: gain 1 soul energy per 40 seconds
 * [Level 4]: gain 1 soul energy per 30 seconds
 * [Level 5]: gain 1 soul energy per 20 seconds