Mana cost of a flashbacked flash of insight?

[shteev]

If I flashback a flash of insight from my graveyard removing 4 blue cards, what is the converted mana cost of the spell? Is it 2, or is it 6? I understand that if I was to play it from my hand with X=4, the converted mana cost would be 6, but I'm unsure of whether the X in the casting cost of the spell is considered for converted mana cost when it's flashbacked?

P.S. Flashbacked? or Flashedback? Inquiring minds want to know!

[Julian23]

cmc is 6

[Wrath_Of_Houlding]

Ditto the 6.

Also, I would vote for "flashedback" out of the two, although most proper is probably "when the flashback cost is played".

[herbig]

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