please help

Bullet = {"bullet"}
divide = 1
childNumber = -1
layer = "BelowPlayer"
position = "BelowPlayer"
below = false
CreateLayer(Warning,position,below)
playSound = true
ignoreDef = false
timer = 0
moving = 0
moveplayer = true
Arena.Resize(100,100)


function Update()
moving = moving + .10
Arena.Resize(100-moving,100-moving)
timer = timer + 1
if timer == 1 then
timer = 0
CreateProjectile("bullet",50,-50+math.random(100))
Bullet.Move(-100, Bullet.y)
Player.sprite.color = {213/255, 53/255, 217/255}
end
end
function OnHit(bullet)
    Player.Hurt(10)
end