Some unofficial “pack 4” releases bundle multiple EPs/SPs. In that case, a paper would explain:

Most legacy content from that era consists of .package files. These files are typically installed manually into a specific directory to ensure the game engine can recognize the new assets. Players often sought out these packs for:

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The installation requires a modicum of technical know-how (a 4GB patch, file extraction, and folder management), but the payoff is immense. From the flickering neon signs to the flapping mesh sleeves, every detail in Pack 4 feels intentional.

Advanced skin overlays and clothing files designed to provide a more life-like aesthetic than the original Maxis textures.

This would be a very reasonable guess, as even today many players refer to expansion packs and stuff packs simply as "packs."

Many modders release "packs" that are collections of their smaller mods, compiled together for easier download. "Pack 4" could very well be one such compilation.

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