Worked on the EQEmu/Server repository to enhance the spell resistance system in a C++ backend environment, focusing on combat mechanics and game development. Developed a multi-check resist system that allows multiple resistance checks per spell effect, refactored core logic from GetSpellEffectResistChance to TrySpellEffectResist, and integrated item and AA bonuses into spell resistances. Addressed edge-case inconsistencies by clarifying fear resistance behavior for pets and fixing the handling of unresistable spells to match live server expectations. These updates improved the accuracy and maintainability of spell mechanics, laying a foundation for future balance and smoother quality assurance processes.