i noticed that you CAN attach color crystals to your blasters in swtor so here is a fun guide on how YOU can customize your blaster colors with lore. its not saber colors but it IS fun!
blaster bolt colors are largely decided by the kind of gas they use (think different flavors of tibanna gas -- it has a lot of different types and manufacturing procceses), so my best guess is the cheaper refining process the less good the gas. think of it as options at the gas station, from cheapest to most expensive!
red bolts are the most common. they use the cheapest and easiest to source gas. this will be the kind you see the most. its unrefined tibanna all the way down.
blue bolts are ion shots! they disrupt machinery and are best used against droids and electronics. more expensive than red gas. this one is ionized tibanna!
green bolts are the expensive, premium option. these bolts have a physical impact behind them and can hit hard enough to punch through targets and/or push those targets back. it's super refined. this is refined tibanna!
yellow bolts are used almost exclusively by mandalorians and the gas is mined from the mandalore system. there is speculation that these bolts are a higher quality and function more like their green counterparts than the standard... it's a higher grade of ammunition, a tibanna variant for mandos!
orange and light blue bolts occupy the same catagory: its all training bolts. that said they do function slightly differently.
orange is a non-lethal, low power option.
wheras light blue is a watered down version of the standard blue bolts for training against droids (wherein you wouldn't have to repair the droid so much, as it causes less damage.)
dont ask me about purple ok. i dont know. puts my head in my hands. the geonosians get purple and no one knows why. a specific vein ala mandalorian yellow bolts? is it because they're bugs? if so do the killiks also get purple? and why the hell do some DROIDS get PURPLE. for me personally im siding with the bugs. the bugs get purple.
also chiss get green and blue charric bolts, which is basically an energy beam and not tibanna gas. its really hot and it hurts a lot and lightsabers do not deflect it. it punches through most armor and electrifies any metal armor it can't punch through to zap whoever is inside. (get a mandalorian a rubber kute the chiss do not want you to know this but you would be unstoppable-- the secret police are taking me away dont let them up-!)
There are a LOT of color combinations in the game! It's all tibanna gas so get funky with it. give your blaster rounds special effects if you want! say they were refined differently or are from a specific place! i want to see SO MANY custom blaster colors i am customizing all my little guys blaster colors now and i am taking you all with me!!!
tangentwithtanner
stormborns
