Update: It seems there's a bug within the game that removes your weapons skins upon leaving the game. Luckily, the weapon skin you have equipped will always stay on your guns, until you change it. So upon quitting the game, equip the one you like the most, so it doesn't disappear. This is a bit of a hassle but there is no fix for this at this current time.
Old: A plethora of games nowadays has some sort of skins feature, where you can customize your outfit or weapons to some degree or another. The Ascent is among them that have this option, but how exactly do you do it?
To equip weapons skins, you must first be in Cluster 13, in the Warren Tier, and then locate the Gun Smith vendor and interact with them. This vendor is symbolized on the map with a hammer icon. They are east of the Weapon vendor and south of the Augment vendor.
Upon speaking to him, you have the option to upgrade your weapons or to equip weapon skins. Choose weapon skins, and if you have any—pick the one you want, and all your weapons will have that weapon skin. There is no way to individualize skins for each weapon. They all have to look the same.
To find weapon skins, you need to pick them up as loot on your travels through The Ascent. They could be loot from opening a chest or dropped from killing all enemies that cross your path.
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