The internet forms an important component of ideological radicalisation, as it provides a platform for like-minded individuals to communicate in virtual communities like the ‘Chanosphere,’ which in turn allows for extremist groups to develop safe havens of communication and information exchange [1]. Using the case study of a cluster of alt-right terrorist attacks initiated by the Christchurch mosque shootings in 2019, this analysis will demonstrate that alt-right memes played a central role in radicalisation, in that they acted as vessels of encoded racist ideology which used ‘weaponised irony’ as a means of communicating group identity