Given "Dragon Storm" as part of Prologue: Act I - The Outlander Who Caught the Wind, here’s how this quest unfolds.
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Unlocking the Quest 
1.Prerequisite: You need to have completed the previous segments of the Prologue, likely after resolving some initial crisis or investigation related to the disturbances in Mondstadt.
2.Quest Walkthrough
3.Crisis Briefing: Return to Mondstadt after your adventures or directly transition from the last quest. You'll likely meet with Jean or Lisa, who will inform you about the escalating situation with Stormterror (Dvalin). The dragon's wrath is causing a storm that threatens the city.
4.Gathering the Team: You might be tasked with uniting or informing key characters like Amber, Kaeya, and possibly Diluc if he's involved at this stage, to prepare for the confrontation with Dvalin. Each might provide insights or aid in preparing defenses or strategies.
5.Preparation Phase: Gathering Resources: You might need to collect or prepare special items or elemental concoctions that could weaken Dvalin or protect against his attacks.
6.Defense Setup: Help set up barriers or elemental totems around Mondstadt or a specific battlefield designed to counter Dvalin's storm.
7.Confronting Stormterror: Head to Stormterror's Lair. This could involve navigating through a storm-ravaged area, using wind currents to ascend to where Dvalin resides or has been provoked into appearing.
8.Battle with Dvalin: This isn't an all-out fight to defeat him but rather to calm or repel him. You might:
9.Use wind gliders to reach strategic points to place or activate devices that counteract his storm powers.
10.Engage in a phased battle where you're weakening his storm shield or calming his fury, possibly using elemental reactions or special items prepared earlier.
11.Calming the Storm: Through teamwork with other characters, manage to calm or temporarily repel Dvalin, reducing the immediate threat to Mondstadt but not resolving the issue completely.
12.Aftermath and Planning: Return to Mondstadt to discuss what happened with Jean and others. Here, you learn more about Dvalin's past, why he's attacking, and what might be done next.
13.Quest Completion: The quest concludes with setting the stage for further investigation into Dvalin's corruption, with characters like Venti providing more context or hints towards needing more allies or power to fully resolve this conflict.
Quest Rewards
•Adventure EXP: Substantial for advancing your rank.
•Primogems: Reward for quest completion.
•Character EXP Materials: To level up characters involved in defending Mondstadt.
•Mora: For general use.
•Artifact or Weapon Enhancement Materials: Possibly, for your efforts in the battle.
Quest Tips 
•Team Composition: Ensure your team can handle elemental reactions well, especially if there are mechanics requiring you to break elemental shields or use specific elements against Dvalin's attacks.
•Gliding and Navigation: Familiarize yourself with gliding mechanics as you'll need to navigate through turbulent winds.
•Co-op Consideration: If this stage allows for co-op, bringing friends can make managing the battle phases easier, especially if you're finding the mechanics challenging.
•Follow-Up: Pay attention to the dialogue after the quest as it will set up future quests or give hints about Mondstadt's lore and the Abyss Order's involvement.
This quest deepens the narrative around Stormterror, revealing the complexities of his relationship with Mondstadt and setting up for more extensive adventures into Genshin Impact's storyline.
