The script doesn't work in server but only in testing mode. It's a localscript placed in StarterGUI.
`local p = script.Parent.Parent
char = p.Character
repeat wait() until char
hum = char.Humanoid
local mouse = p:GetMouse()
colors = {"Really red","Dark stone grey"}
mouse.KeyDown:connect(function(key)
if key == "v" then
ball = Instance.new('Part', char.Torso)
ball.Size = Vector3.new(3,3,3)
ball.BrickColor = BrickColor.new('Really red')
ball.Material = "Neon"
ball.CanCollide = false
ball.Anchored = false
ball.Position = char.Torso.Position
ball.CFrame = CFrame.new(ball.Position, mouse.Hit.p)
local bv=Instance.new("BodyVelocity",ball)
bv.maxForce=Vector3.new(math.huge,math.huge,math.huge)
bv.velocity=ball.CFrame.lookVector*130
mesh = Instance.new('SpecialMesh', ball)
mesh.MeshType = "Sphere"
ball.Touched:connect(function(hit)
if hit.Parent ~= char and hit.Parent:findFirstChild("Humanoid") then
ball:Destroy()
for i= 1, 5 do
x = script.Explosion:clone()
x.Parent = game.Workspace
x.BrickColor = BrickColor.new(colors[math.random(1,#colors)])
x.Mesh.Scale = x.Mesh.Scale+Vector3.new(4,4,4)
x.Position = hit.Position
x.CFrame = x.CFrame*CFrame.Angles(math.random(-3,3),math.random(-3,3),math.random(-3,3))
x.Grow.Disabled = false
hit.Parent.Humanoid.Health = hit.Parent.Humanoid.Health - 5
game.Debris:AddItem(x,2)
end
wait(6)
ball:Destroy()
end
end)
end
end)`

2 comments
Where's the script placed? What type of script is it? Are StreamingEnabled or FilteringEnabled true?
Script is in StarterGUI, it's a LocalScript. FilteringEnabled is false. StreamingEnabled is false.