you have to be at least level 22 i think
This is an opinion based question but may say that the Reflex sight is the best reticle on the game "Call of Duty : Black Ops"
In Call of Duty: Black Ops 2, you can customize your reticle by using the "Create a Class" menu. After selecting a weapon, go to the "Optics" attachment option and choose a sight that offers reticle customization. Depending on the sight, you may have the option to select different reticle designs or colors. Make sure to unlock any required challenges or levels for certain sights to access their unique reticles.
All of the major scope in Black Ops 2 have their own Reticle Challenges. In order to change reticle colors, you'll need to finish all of the Reticle Challenges. You can access the Challenges in the Barracks menu.
In Black Ops multiplayer you unlock the AK-47 at level 38.
3arc unlock
type in 'doa' on that computer or '3arc unlock'
You unlock gold camo in black ops, when you reach prestige level 14, level 25.
41
When you first get the AUG it has a scope(not available in multiplayer) with a circle with no inside as the reticle. When it gets pack a punched it keeps the scope but the reticle changes and you get a powerful masterkey shotgun that reloads 2 shots at a time.
You have to get to level 44 and then pay the $2000 to unlock it
When you rank up to level 35 you will unlock it.
You need to unlock the weapons.