Obscurial attack on New York

"We've lived in the shadows for far too long."

- Gellert Grindelwald to Credence Barebone

This attack occurred in December of 1926 after Dark wizard Gellert Grindelwald infiltrated MACUSA by assuming the identity of Auror Percival Graves, allowing him to manipulate Credence Barebone.

Background
In 1926, Dark wizard Gellert Grindelwald infiltrated MACUSA by assuming the identity of Auror Percival Graves. Grindelwald believed the mysterious attacks occurring in New York City to be the work of a powerful Obscurial, which he felt would be a great asset for his plans of world domination. Using his disguise as Graves, Grindelwald came into regular contact with Credence Barebone. He believed Credence to be connected to the Obscurial due to a vision he received. Believing Credence was an orphaned Squib, Grindelwald emotionally manipulated him into helping him find the Obscurial. He did this with the promise of protecting him from his abusive adoptive mother and teaching him magic.



During this time, Grindelwald (as Graves) arrested Newt Scamander, whose escaped beasts were believed by the MACUSA to be the cause of the Obscurial's attacks. During his interrogation, Grindelwald discovered the Obscurus within Newt's suitcase, and in an effort to hide his tracks, had him and Tina Goldstein sentenced to death. Afterwards, he approached Credence after Mary Lou Barebone was killed by the Obscurial and had him track down his adoptive sister Modesty Barebone, believing her to be the source of the Obscurus.

The attack
Once they found Modesty, Grindelwald cruelly rejected Credence, as he had no further use of him. This angered Credence, who then revealed that he was the Obscurial, much to Grindelwald's surprise. Grindelwald attempted to convince Credence that he had nothing to fear anymore and to join his ranks, but this further angered Credence who began rampaging through the city. When Grindelwald, Newt, and Tina were finally close to calming down Credence, President Picquery and her other Aurors appeared on the scene, and she orders them to attack the Obscurus. Acting on her orders they did as they were told and opened fire.



With Credence being seemingly destroyed at the Aurors' hands, Grindelwald was so beside himself with rage, that he, lead by his extreme idealism, began to break his disguise, expressing his utter disgust for being forced to hide from the No-Majs. Picquery subsequently ordered the other Aurors to bring "Percival Graves" in, but Grindelwald, no longer suppressing his tremendous magical prowess, gave battle against all of the Aurors simultaneously (much to the President's shock and dismay), and gradually brought them down one after the other, until Newt finally managed to catch him off-guard with his Swooping Evil and restrained Grindelwald's hands from behind, while Tina used a Summoning Charm to take Graves' wand. Newt casted the Revelio Charm, making Grindelwald's disguise fade away, revealing his true face. Even apprehended, Grindelwald was unfazed, arrogantly questioning President Picquery's ability to contain a wizard of his reputation and power. As he was lead away, Grindelwald met Newt's gaze and mysteriously asked him: "Will we die, just a little?"

Aftermath
Grindelwald dramatically escaped the MACUSA a few months later. At some point, he established a prison, Nurmengard, to serve as a form of containment for his enemies.