Its classification is as a Summoning Ritual Magic, effective only on Holy Relics made by dragon-hunters, and it can only be activated by spellcasters with dragon blood flowing in their veins.
And the price that the spellcaster must pay is extremely heavy.
Most dragon-hunters who have used this ability could never revert back...
"...This guy is probably using a scale or a tooth from some great dragon as a medium, and the offering is the blood from his own body and that of the Lizardmen present here... Tsk tsk, who would have thought that the blood of these geckos actually contains a few drops of dragon blood."
That's not Dragon Language Magic at all!
The so-called dragons summoned in this way are not real dragons but rather something akin to the Undead!
It's laughable.
Compared to myself, who borrows the power of Dragon Language, this guy is the true blasphemer!
The giant dragon not far from here has already begun to rampage.
