Call of duty 4, a grate classic.
The multilayer mode for this game would be its strong point. You can unlock guns you see in the campaign but you have the ability to edit attachments like the sights and magazines.
This was the first Call of duty to have customisable weapons and load outs. It was also the first to modern war shooter of the series.
The campaign was amazing compared the the previous games with its big graphics upgrade and physics improvement and this wasn't just for the campaign it was for multilayer to.
Online you could customise you character load outs so you could make a kit for stealth with silencers and C4 or a class for tanking with a Light machine gun and juggernaut. You were aloud to switch between these classes in game if you feel like your tactics aren't working.
The game was brilliant for its time but now the online mode has almost been wrecked by modders and hackers. You would join a hacked game 1 every 4 so its not as bad as PlayStation.r