Black Mesa: Classic Addon is a modpack that adds good stuff (for Black Mesa MOD) what fans will really enjoy. Classic HL1/HL2 soundtrack, remixes, mashups, hard rock covers and reimagined PS2 main theme. Improved and HL1/HL2 Style Textures. New and HL1/HL2/PS2 style sounds for every part of the game. New weapon models and better weapon animations for every weapon for the 1st person experience. Classic Hazard Course and added removed levels. HL1 style game balance. Improved particles. Little improvements.