General

lol... These people are so funny. Listen to me, you're a Zero. That means when you boom your weapon, you'll get a trace of it AND a clean Zero weapon. Just put the trace on the clean one and restart starring it to 15. I've gotten plenty of weapons to 15 stars before. The only time I boomed was on my tyrant hyades belt.

@divinerikku: 1 bil isn't much compared to before star enhancements. Which you could never get to 15 stars without spending $500. That's even half the cost of a no boom AEE in my world.

got my 140 dagger to 15 stars.. only took about 15 attempts from 11 stars and onwards.. also got legendary inner ability on both my characters.. all i did was watch ZeroByDivide's video lol

wow thinking i've made da/lumi/zero wep 15* already people must have bad luck

I've spent over 10b getting a single item to 15 stars through starforce. Don't do it unless you are prepared to spend that much.

Also, there's no way to prevent it from booming. It's just luck.

Honestly I've had a claw go from 12 stars to 13 stars trying to get it all the way.
It took me 1bil.
My current bow took me 200mil to get to 15 stars so it's random luck.
Also if your weapon booms from enhancing with the star force if you grab a clean one, it'll throw all the stats on it.
It just won't have the enhancements.

You can get it to 12 stars without booming.

as @stuuv12345 has said, going past 12 stars (when there's a chance to boom) is an end game thing. You should focus more on scrolling your gears better and also potting them better or even getting more items (you might not have an emblem or a badge!) you can get to 12 stars without booming but the cost is too much past 10 stars so I suggest investing that on more scrolling/better gear/ better pot ^^

15 stars isn't worth it at your level, you should focus on other upgrades first. Getting a weapon to 15 stars should be a very end game thing to do.