User blog comment:Jrotc193/Upgrades/@comment-7418318-20130624093153

Who says that they don't have it already? It might just be less obvious than Dragon Force or Power Parfume. Gildarts is able to pulverize Byro's staff by hitting it with his fist or hit Natsu strong enough that he leaves an indentation in the floor, ceiling or whatever he's smacked into.

But I don't think physical attacks are the best way to attack a Dragon anyway. That being said when he get's really serious about defeating a very strong enemy Makarov used magic other than Titan.

He had three "boss-fights" against Jose, Hades and Acnologia and only against the Dragon he used Titan, but there he tried to hold it down so it "brats" could escape.

Either way, with Dragons being next to immune to anything short of Dragon Slayer magic and attacks from their own kind, I don't think any kind of magic boost that only increases their current powers would be of any help. They'd need something that changes the properties of their attacks (whether physical or magical) to emulate the way DS magic pierces through Dragon defenses. But if something like that existed, why bother creating Dragon Slayers in the first place?