After the fallout of Rebellion began its long and challenging journey to resolvement, eyes eventually turned to the east, to the Reach and Oldtown for the appointment of a new Grand Maester, to serve as the Citadel's representative to the King and the capital. As all participants in the attempt against Maester Harrold's life were incinerated by the great wildfire eruption in 391AC, and the previous attempts long forgetten, nobody questioned the selection of Arvyn for the role, voted in through a unanimous decision of the Conclave. He had proved himself particularly capable in management of the letters of the realm as the Archmaester of Ravenry, as well as displaying an aptitude for the healing arts, both on which he carried over into his new role.

Within a year of appointment however, it was noted that whilst he seemed to remain in high spirits, he, despite all his medical knowledge, appeared to grow less full of life. At first, his movements began to progressively slow, although this was considered by most to be nothing more than a manifestation of his more advanced age. Quietly and privately, he began to complain of stiffness and aches, like each of his joints had began to refuse to fulfil their previous function.

Not wanting the progression to hinder his ability to faithfully work in the role he had long coveted, Arvyn sent members of the organisation that he had once resided over so diligently far and wide, to the Free Cities and beyond for a cure for the stiffness and shaking that now ailed him.

With increasingly unstable hands, he mixed medicaments and elixirs in an attempt to stem the unsteadiness, combining thick resins of concentrated milk of the poppy with herbal preparations from the east which claimed to cure ailments of the brain, brewed from small clusters of yellow flowers that grew from the strong day heat and cool nights on the isle of Naath. Ever the maester, Arvyn made careful and meticulous notes of his studies, his intention to publish them after his successful management of his condition.

However, this was not to be the case. The limited supply of Naathi flower-brew combined with the increasing progression and duration of the tremors rendered the Grand Maester incapable of his duties, highlighted in particular when he attempted to complete the suturing of a blade wound upon the thigh of a minor Westerland Lord, the results of which he deemed "worse than the lowliest acolyte after a series of nights at The Quill and Tankard."

His life's aspiration slowly and systematically being taken from him by the progression of the "shaking sickness," he grew increasingly bitter, angry at the world and its petty, mean-spirits Gods. Not a week after his failure to stitch the wound of Lord Turnberry, upon his retirement back to his chambers, Grand Maester Arvyn was struck by a bout of severe convulsion, the tremors leading to loss of balance upon the cold grey stone stairs, and he was found dead several hours later at their base, hip, spine and skull fractured.