This came up in a post game discussion last night. Told them I would be posting it here for them to see.
Here is the scenario: I am attacking with Nova, The Human Rocket. My opponent assigns a blocker (Gobby) and has the Smash Global available to be used. He believes he can use Smash to target his Gobby and negate any damage that would be given to Nova.
I tell him only the attacking character can be blocked, therefore his only target would be Nova. Nova would take damage and then deal to damage to my opponent.
He says damage happens simultaneously, so he is also attacking, so he is also being blocked by Nova and can use the Global on his Gobby.
Which is correct?