The aim of this essay is to analyse the conflictive relationship between online anonymity and online harmful conducts that fall outside the scope of existing regulation. With this objective in mind, this essay analyses the increasing recognition of online harmful practices as a problem that needs to be tackled, and how anonymity, while virtuous in keeping the privacy of users to the best of its ability, can also enable online harmful conduct by providing a sense of a lack of accountability. Moreover, we explore the connections between the notions of freedom of speech and freedom of expression with anonymity and online harmful practices, as well as the challenges to regulate the latter with a limitation of the former. Finally, we take a glimpse at Lessig's regulation modalities (law, social norms, and architecture or "code"), and examples of how each of them encapsulate online harm and if measures regarding anonymity should be added to said modalities, in order to properly face online harmful practices as an increasing problem for the current and new generations with the ever-expanding presence of internet worldwide.