Copy "surge" wit h Geistblast
Here we go:
706.10. To copy a spell, activated ability, or triggered ability means to put a copy of it onto the stack; a copy of a spell isn’t cast and a copy of an activated ability isn’t activated. A copy of a spell or ability copies both the characteristics of the spell or ability and all decisions made for it, including modes, targets, the value of X, and additional or alternative costs. (See rule 601, “Casting Spells.”) Choices that are normally made on resolution are not copied. If an effect of the copy refers to objects used to pay its costs, it uses the objects used to pay the costs of the original spell or ability. A copy of a spell is owned by the player under whose control it was put on the stack. A copy of a spell or ability is controlled by the player under whose control it was put on the stack. A copy of a spell is itself a spell, even though it has no spell card associated with it. A copy of an ability is itself an ability.
Surge and madness are alternate costs, and are copiable. If you copy a spell cast via surge or madness, the fact that you cast it via an alternate cost is copiable. So copying a Crush of Tentacles cast via surge will means the copy was also cast via surge (although unless you can deal with the original, your token will get bounced), and copying Avacyn's Judgment cast via madness with X=5 means you also get an Avacyn's Judgment that was cast via madness with X=5.
Nathan Long
Magic Rules NetRep