Second Trade War

Second Trade War is an event that takes place during the year X686, post-Tenrou Jade arc.

Prologue
Still recovering from Zera departure, the other Mages are curious of Mavis's idea of opening a Mage guild within the city of Magnolia. Yury weary of her idea, but Mavis points out that everyone must have a home to return too, which is her reasoning behind creating a guild in the city, wanting to be able to liberate all of the citizens from the despair caused by Blue Skull while creating a more comfortable ecosystem. The treasure hunters all come to agreement with her plan, leading her to name the guild "Fairy Tail" due to the mystery if fairies have tails, leading to a never-ending adventure. Around this time, many differing feudal lords began a struggle over trading rights, whereas the Second Trade War began, even including mercenary Mages and Guilds taking sides in the battle.

Trade War
Mavis Vermilion is seen thinking and planning their next motives, which she tells the soldiers to set up a flank at a certain spot, which two of soldiers call it inhumane and foolish to do. Mavis states she only can come up 49 different scenarios, which is why she wants to take this path on wanting this squadron of soldiers to fall back. Yury Dreyar compliments her prowess, with Precht Gaebolg and Warrod Sequen adding to her stance. Yury readily asks Mavis if it's their time to move out, which Mavis agrees they have to stop the enemy's Mage division, giving them a good chance to do so. Yury's squadron moves out, garnering belief from Mavis and skepticism from the two soldiers. After engaging their foes, the come out victorious; the two soldiers procuring the alias "Fairy Tactician" to Mavis due her incredible I.Q. and knowledge from their victory.

Mavis, in a down mood, sits on a table counter as the rest of the guild members are partying, coming out victorious the day's battle. Yury comes over to ask her what's wrong, which she simply replies she doesn't like the killings and death that came from the battle, only wanting to go on an adventure with her friends. Six years later, the Second Trade War finally comes to an end, with both sides taking humongous tolls of death from it.

Aftermath
With the war over, the Magic Council passes the Interguild Dispute Interdiction Treaty, forbidding all and every guild from waging wars against one or another, for whatever reason, marking a beginning of a short era of peace. Some time after the, Mavis manages to meet Zeref again. Later after greetings, Mavis gets shocked to know that he is Zeref, the Black Wizard, but doesn't believe the rumors of him being evil, rather thinking of him as a kind person. Briefly after, Zeref wonders how her appearance didn't change ever since their last encounter. As Mavis then explains it as a consequence of using Law, Zeref gets greatly astounded, shortly after which he tells her that she's become immortal just like him, being cursed by Ankhseram as well. Continuing on, Zeref tells Mavis that the more she doesn't want to take people's lives, the more people will die. Completely shocked to hear that, Mavis neglects the fact that even if she doesn't believe him to be cruel, the Black Mage declares what is said about him is truthful. Sorrowful to now know the truth, Mavis leaves the latter, still under the belief that the life of her friends is precious, all the while running through Magnolia.