With great skill, and a bit of arcane magic, the hero uses a sling to shoot two projectiles perfectly aimed at two different enemies.
Having mastered the two targets hits, give a bonus when attacking only one, it allows to concentrate better the power damage of one rock
Increase the bonus on the effect, not the level of the skill. The bonuses will be added to the amount of damage (when using that type of attack)or the amount of healing (when healing).