During the past two decades, the main focus in the fast-growing field of multimodality has been the inter-semiotic relationships between different modes. However, due attention has recently been paid to one element which is lacking in multimodal texts: the argumentative element. This is referred to in the literature as multimodal argumentation in the belief that an argument is neither verbal nor visual and, in analyzing argumentative discourse, attention is to be paid to both verbal and visual modes with no need for a priori division. This research attempts to provide further study in this direction, thus adding to the current interest in giving a new perspective to the analysis of argumentative discourse. This research aims to explore how Instagram posts, viewed as representing perlocutionary acts, operate as instances of multimodal argumentation. The study is structured within the Contemporary Theoretical Framework of the Speech Act theory (Harris et al., 2018) and Multimodal Argumentation (Tseronis, 2018, 2020). Data for the study are images from The Incredible Hulk Comic Book (1980) and Instagram spoof posts (photos and captions) by Arab Netizens on 11th to 13th November (2022) towards the first trailer for Captain America 4: New World Order (2024), which were in response to Marvel Studios’ announcement in September 2022. A descriptive qualitative approach has been adopted as it describes a particular perspective qualitatively. Findings have revealed that spoof Instagram posts operating as a perlocutionary act are potential instances of multimodal argumentation. The research might add to the domain of speech acts and the literature on multimodal argumentation.