He took part in the mages assembly on Thanedd Island but during the night a Redanian commando, lead by Sigismund Dijkstra and Keira Metz, arrested and handcuffed him with Dimeritium shackles. Keira then punched him in the face with brass knuckles, defacing his nose and his lips. This treatment was applied then to all the other mages accused to cooperate with Nilfgaard. This was the beginning of the so-called Thanedd coup.
Later, things got even worse: all the mages enchained with the dimeritium were freed by Tissaia de Vries. Francesca Findabair then opened the dungeons gate of the palace, letting in a Scoia'tael commando lead by Cahir Mawr Dyffryn aep Ceallach and by Rience, who were waiting for the ambush.
Later Artaud managed to capture Ciri, who was secretly infiltrated on the island by Yennefer, but Philippa, while in her owl form, attacked him, scratching with her talons at his eyes. Geralt of Rivia then cut through Artaud's neck with his sword, right under his nape.