So I know by all means this should absolutely without a doubt work, because I'M USISNG A NEARLY IDENTICAL SCRIPT FOR A DIFFERENT PROJECT. I've tried it using a regular script, and localscript.
I've tried using Base = script.Parent.Base and also Base = script.Parent["Base"'], but no matter what I do, this will not work Its absurd!
Here's the script:
game.StarterGui:SetCoreGuiEnabled("All", false)
Base = script.Parent["Base"]
Base.Visible = true
IDF = Base["IdentityTheif"]
C = Base["Creator"]
Base.backgroundTransparency = 0
Wait(2)
IDF.TextTransparency = 1
Wait(0.1)
IDF.TextTransparency = .8
C.TextTransparency = 1
Wait(0.1)
IDF.TextTransparency = .5
C.TextTransparency = .8
Wait(0.1)
IDF.TextTransparency = .2
C.TextTransparency = .5
Wait(0.1)
IDF.TextTransparency = 0
C.TextTransparency = .2
Wait(0.1)
C.TextTransparency = 0
Wait(5)
IDF.TextTransparency = .2
Wait(0.1)
IDF.TextTransparency = .5
C.TextTransparency = .2
Wait(0.1)
IDF.TextTransparency = .8
C.TextTransparency = .5
Wait(0.1)
IDF.TextTransparency = 1
C.TextTransparency = .8
Wait(0.1)
C.TextTransparency = 1
Wait(2)
Base.BackgroundTransparency = .2
Wait(0.01)
Base.BackgroundTransparency = .5
Wait(0.01)
Base.BackgroundTransparency = .8
Wait(0.01)
Base.BackgroundTransparency = 1
Base.Visible = false

2 comments
Line 8, capitalize
BackgroundTransparencyOh my god. XD