While attending music school in 1996, Michael asked Christopher to record solos for his new melodic death metal project Arch Enemy.

After completing an extensive world tour with Arch Enemy, Amott returned to his Armageddon project, and released Three in 2002 on Toy's Factory records in Japan.

This time featuring Christopher on lead vocals, the album was almost purely a power metal effort, focusing on the melodic singing and guitar work of Amott.

[3] In 2014, Amott began recording for the new Armageddon album with a new lineup consisting of himself, vocalist Matt Hallquist, guitarist Joey Concepcion, bassist Sara Claudius, and drummer Márton Veress.

[5] During Arch Enemy's North American tour in support of their album War Eternal, guitarist Nick Cordle reportedly left the band.

[6] On 10 October 2015, as part of Japan's Loud Park Festival, Arch Enemy vocalist Alissa White-Gluz invited special guests Amott and Johan Liiva to the stage, reuniting the Burning Bridges lineup.

Amott made a guest appearance on Arch Enemy and performed two songs, "Revolution Begins" and "Blood On Your Hands".

Starting on 23 May 2016, Amott along with the original Arch Enemy lineup reunited as Project Black Earth and made a special tour in Japan.

On 30 March 2020, Amott joined Dark Tranquillity, replacing original guitarist Niklas Sundin, but left the band on 23 July 2023.