Code seems to break when creating an enemy out of the range of the Tower

class Enemy {
   var life:Int = 2
   let position: Point

    init(x: Int, y: Int) {
        self.position = Point(x: x, y: y)
    }

    func decreaseHealth(factor: Int) {
        life -= factor
    }
}

class Tower {
    let position: Point
    var range: Int = 1
    var strength: Int = 1

    init(x: Int, y: Int) {
        self.position = Point(x: x, y: y)
    }

    func fireAtEnemy(enemy: Enemy) {
        if inRange(self.position, range: self.range, target: enemy.position) {
            while enemy.life > 0 {
                enemy.decreaseHealth(self.strength)
                print("POW! Enemy health is now \(enemy.life)")
            }
            print("Enemy health is now 0. The enemy has been vanquished!")
        } else {
            print("The enemy was out of range...")
        }
    }

    func inRange(position: Point, range: Int, target: Point) -> Bool {
        let surroundingPoints = position.surroundingPointsWith(withRange: range)
        for point in surroundingPoints {
            if (point.x == target.x && point.y == target.y) {
                return true
            }
        }
        return false
    }
}

// Class Inheritance!
class SuperEnemy: Enemy {
    let isSuper: Bool = true

    override init(x: Int, y: Int) {
        super.init(x: x, y: y)
        self.life = 50 // we're only able to change this b/c the life field is a VAR instead of a LET

    }
}

class LaserTower: Tower {
    override init(x: Int, y: Int) {
        super.init(x: x, y: y)
        self.range = 100
        self.strength = 100
    }
}



let tower = Tower(x: 0, y: 0)
let laserTower = LaserTower(x: 5, y: 5)
let enemy1 = Enemy(x: 1, y: 1)
let enemy2 = Enemy(x: -12, y: 15)
let superEnemy1 = SuperEnemy(x: 10, y: 10)

tower.fireAtEnemy(enemy1)
tower.fireAtEnemy(enemy2)
laserTower.fireAtEnemy(superEnemy1)
tower.fireAtEnemy(superEnemy1)