Trip mine

Mine = Instance.new("Part")
Mine.Parent = workspace
Mine.Position = Vector3.new(0,5,0)

Mesh = Instance.new("SpecialMesh")
Mesh.Parent = Mine
Mesh.MeshId = "http://www.roblox.com/asset/?id=11954776"
Mesh.TextureId = "http://www.roblox.com/asset/?id=11954766"
Mesh.Scale = Vector3.new(0.7,0.7,0.7)

DunDun = Instance.new("Sound")
DunDun.SoundId = "http://www.roblox.com/asset/?id=11984254"
DunDun.Parent = Mine

SubspaceExplosion = Instance.new("Sound")
SubspaceExplosion.SoundId = "http://www.roblox.com/asset/?id=11984351"
SubspaceExplosion.Parent = Mine

Calibrate = Instance.new("Sound")
Calibrate.SoundId = "http://www.roblox.com/asset/?id=11956590"
Calibrate.Looped = true
Calibrate.Parent = Mine
Calibrate:Play()

local calibration_time = 2 -- needs to be still/untouched for this long before calibrating
local cur_time = 0
local max_life = 120 -- these things last for 2 minutes on their own, once activated
local calibrated = false

local connection = nil

function activateMine()
    for i=0,1,.1 do
        Mine.Transparency = i
        wait(.05)
    end
    calibrated = true
    Calibrate:Stop()
end

function pulse()
    DunDun:Play()

    for i=.9,.5,-.1 do
        Mine.Transparency = i
        wait(.05)
    end

    for i=.5,1,.1 do
        Mine.Transparency = i
        wait(.05)
    end
end

function explode()
    connection:disconnect()

    for i=1,0,-.2 do
        Mine.Transparency = i
        wait(.05)
    end
    SubspaceExplosion:Play()

    local e = Instance.new("Explosion")
    e.BlastRadius = 16
    e.BlastPressure = 1000000
    e.Position = Mine.Position
    e.Parent = Mine

    local creator = script.Parent:findFirstChild("creator")

    e.Hit:connect(function(part, distance)  onPlayerBlownUp(part, distance, creator) end)


    for i=0,1,.2 do
        Mine.Transparency = i
        wait(.05)
    end
    wait(4)
    Mine:Remove()
end

function update()
    if (calibrated == false) then
        if (Mine.Velocity.magnitude > .05) then
            cur_time = 0
        end

        if (cur_time > calibration_time) then
            activateMine()
        end
    else
        -- calibrated mine
        if (math.random(1,20) == 2) then
            pulse()
        end

        if (cur_time > max_life) then pulse() Mine:Remove() end
    end
end


function OnTouch(part)
    if (calibrated == false) then
        cur_time = 0
    else
        explode()
    end
end


function onPlayerBlownUp(part, distance, creator)

    if (part:getMass() < 300) then
        part.BrickColor = BrickColor.new(1032)
        local s = Instance.new("Sparkles")
        s.Parent = part
        game.Debris:AddItem(s, 5)
    end


    if creator ~= nil and part.Name == "Head" then
        local humanoid = part.Parent.Humanoid
        tagHumanoid(humanoid, creator)
    end
end

function tagHumanoid(humanoid, creator)
    -- tag does not need to expire iff all explosions lethal

    if creator ~= nil then
        local new_tag = creator:clone()
        new_tag.Parent = humanoid
    end
end

function untagHumanoid(humanoid)
    if humanoid ~= nil then
        local tag = humanoid:findFirstChild("creator")
        if tag ~= nil then
            tag.Parent = nil
        end
    end
end

connection = Mine.Touched:connect(OnTouch)


while true do
    update()
    local e,g = wait(.5)
    cur_time = cur_time + e
end