This study, Analysis of Slang Word Translation Spoken by Lamar Davis in the Game Grand Theft Auto V, examines the fan-made Indonesian translation of Lamar Davis’s slang in terms of the categories of slang formation processes, the translation techniques used by the translator, the existence or absence of translation shifts, and the accuracy and acceptability of the translations. Slang is highly informal, culturally rooted, and constantly evolving, making translation complex. The research emphasizes the importance of accurate game localization to preserve cultural authenticity and narrative immersion, focusing on identifying slang formation processes, translation techniques, and their impact on quality. The literature review applies Mattiello’s (2008) and Lutfiah, Septiani, and Putra’s (2024) frameworks for slang formation, Molina and Albir’s (2002) and Butkuvienė and Petrulionė’s (2010) models for translation techniques, and Nababan et al.’s (2012) quality assessment model. The eclecticism framework (Polo & Ailodion, 2024) integrates multiple approaches to address cultural and linguistic complexity, providing a robust foundation for this analysis. This descriptive qualitative study uses content analysis and focus group discussions (FGDs) to evaluate translation shifts, translation accuracy and acceptability. Data were drawn from Lamar Davis’s dialogues in GTA V, totaling 204 slang instances. FGDs with expert raters ensured reliability, while numerical scoring supported a systematic evaluation of translation strategies and quality. Results show semantic shift as the most common slang formation (66.67%), followed by compounding (15.69%) and clipping (14.22%). Softening (39.22%) and borrowing (35.78%) dominate translation strategies, with borrowing producing high accuracy but lower naturalness, while softening increased acceptability but caused shifts. Overall accuracy averaged 2.15, and acceptability 2.20, indicating moderate translation quality. The study concludes that slang translation in games demands balance between fidelity and cultural adaptation. Translators should consider localized terms or explanatory elements to preserve meaning and context. This research contributes theoretically to slang and translation studies and offers practical guidance for game localization teams and fan translators to achieve culturally resonant and immersive player experiences.