Video game quality assurance (QA) is vital to ensuring a high-quality gaming experience across different languages and regions. Competent localisation testers are expected to have advanced language skills, exceptional attention to detail, and familiarity with the game they are testing. However, individual testing performance differs, prompting the question of what constitutes a proficient localisation tester. In this study, students (N = 43) from the degree in Translation and Interpreting from the University of Alicante and the Specialist degree in Translation for the Video Game Industry from the University of Vigo were asked to test a localised video game which contained deliberate errors introduced for the purpose of this study. Subsequently, they completed questionnaires regarding localisation-related attitudes, personality traits, and trait anxiety levels. The results of various bivariate correlation and multivariate linear regression analyses indicate that translation expertise, low emotional stability, and a preference for screen reading were significant predictors of higher error detection rates. Furthermore, other variables such as attitudes towards video games, punctiliousness, and reading speed correlated with error detection in video game localisation testing. These findings may contribute to the enhancement of tester selection and training processes, resulting in superior localisations and more satisfying player experiences across diverse languages and cultures.