1858158:Play MST first, destroy Macro Cosmos, then activate Burial from a Different Dimension.
You cannot activate effects if they are going to do nothing, even if you plan on doing something later in the chain that might make it valid. If my opponent has nothing on his field, I can't activate Raigeki even if I'm planning on chaining Ojama Trio to it.
He's never been wrong since I've been here, so I'll trust him.
And, the ruling makes perfect sense
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