Auzou Book for dragon stones tome 1 la métamorphose

For his twelfth birthday, Sengé receives a special stone from his grandfather. He soon discovers that it's a dragon stone, and that he's lui-même a half-human, half-dragon child whose powers have just been revealed. Beware: for the time being, he's one of the brave dragons-sentinels, but if he can't control his strength and pride, he could well turn to the darker side: the dragons-conquerors. His middle-school enemy, Vlad, is one of them, and the two boys are about to go head-to-head...