Contributed to the mamedev/mame repository by expanding Sega X-board clone coverage, specifically adding support for the After Burner (set 2) ROM clone. This work involved implementing new ROM definitions, mapping memory regions, and updating hardware documentation to ensure accurate emulation. The developer registered the new clone in the emulation game list, enhancing both the breadth and maintainability of the Sega X-board driver. Utilizing C++, emulation development techniques, and reverse engineering skills, the contribution focused on isolating ROM and clone logic, which improved code clarity and future maintainability. No bugs were fixed during this period, with efforts centered on feature expansion.