User blog comment:FairyRaven/Fairy Tail Chapter 328: Zodiac, Review and Commentary/@comment-112.205.41.120-20130421090106/@comment-4829046-20130421115634

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"A spark of light suddenly appears and Igneel's voice comes from it, asking what's wrong and if he'll be defeated by something like that. He asks him if he can call himself the child of Igneel in that state. Natsu has a momentary flashback of when he was young and he was supposed to destroy a mountainous rock."