Erin and Rockhammer

When Erin and her dragon Rockhammer get into a fight with another dragonseer, they're sent away to Stillness. There they discover the Solace Stone, a magical object that creates calm. In the peace of Stillness, Erin almost forgets that she can't summon her dragon Rockhammer. But when mysterious soldiers storm Stillness, destroying her home in the process, Erin must find a way or risk being trapped forever.