So my opponent has an Edric and a Snapcaster.
I have an Agent of the Fates and Fire // Ice.
How does the Fire work here? If I would cast Fire and attempt to deal 1 damage to Snapcaster and 1 to my Agent to trigger Heroic, would my opponent have to sacrifice Edric?
The tricky part is when the trigger goes off, before or after the lethal damage would be dealt to Snapcaster.
The trigger happens when you cast...so it is going to resolve before fire. This means he has the choice of saccing snappy or edric.