User blog comment:Lord Zeref Dragneel/Top 25 most powerful characters/@comment-26451407-20150811032133/@comment-1153699-20150811070007

Natsu's strongest attack in that form (during Tartarus arc) didn't really affect Mard tbh. That's why I put current DF Natsu more or less on Laxus's lvl. Or maybe a tiny bit below him (for now). But I doubt Natsu can use DF for as long as he wants. I think he can only use it for short bursts in power (like GMG Natsu's LFD) simply because of how much Magic it consumes from him with every attack.

And if Natsu can only use DF for a few attacks, I don't see him beating Laxus. After using DF, he's most probably going to be weakened. And from then on, it's just not gonna be pretty...