pocketmine\event\entity\EntityDamageByEntityEvent::addAttackerModifiers PHP Method

    protected function addAttackerModifiers(Entity $damager)
    {
        if ($damager->hasEffect(Effect::STRENGTH)) {
            $this->setRateDamage(1 + 0.3 * ($damager->getEffect(Effect::STRENGTH)->getAmplifier() + 1), self::MODIFIER_STRENGTH);
        }
        if ($damager->hasEffect(Effect::WEAKNESS)) {
            $eff_level = 1 - 0.2 * ($damager->getEffect(Effect::WEAKNESS)->getAmplifier() + 1);
            if ($eff_level < 0) {
                $eff_level = 0;
            }
            $this->setRateDamage($eff_level, self::MODIFIER_WEAKNESS);
        }
    }