Gisela + Balefire Dragon = ?

[The Big Ragu]

How much damage are we looking at here?

[cdr]

Please put more effort into questions. At minimum, cite any relevant Oracle texts - especially when you're asking about a spoilered card. Also, you can probably be more descriptive than eight words.

Anyway, assuming this is your question: a replacement effect will apply to each applicable event once. The Dragon dealing combat damage is one event (6x2=12), and the Dragon's trigger is a separate event (12x2=24).