The Battle will continue until one Side Fails To Fight.Hmm, I am still not sure about Natsu's DF. Can someone make that clear? Can he activate it at will? Maybe some proofs like pages would help a little..
Well so @natsulucy assumed Natsu can activate DF at will? Does this match end when one of side can't continue, are unconscious, or? If it's "one of side can't continue", then I agree with @SirSamuel016 , LFD would be the last. DF has no time to be activated.
And As @SirSamuel016 said this topic will get off topic.But I assume He can DF based on Tartaros and Wendy.