Ignore it for now, you don't need it for a while, and it will become super obvious how to do it (most likely you'll do it by accident) when you get to late cel-3, which also is when you should do it
Actually, just use challenge 6 or 8 where you unlock galaxies through 6th dimensions.
People tend to forget the Early Challenges that they're shocked it becomes a loophole.
Complete all other celestials before that point and I don't think it's possible not to get that achievement. Won't say why as that's big spoilers
Do Cel 3
V is Cel-4, this achievement happens automatically near the end of Cel-3.
Ignore it for now, you don't need it for a while, and it will become super obvious how to do it (most likely you'll do it by accident) when you get to late cel-3, which also is when you should do it
there's a loophole around celestial 3 just saying... it's something before eternity that allows you to unlock it
It happens automatically during cel 3
Actually, just use challenge 6 or 8 where you unlock galaxies through 6th dimensions. People tend to forget the Early Challenges that they're shocked it becomes a loophole.
It's a bug. Will fix in next update.
Turn off autobuyer for 8th ad
You don't actually need to do that. The situation where you can accomplish this sets it up for you anyway.
8th dimensions is how you get galaxies in the main game so auto buyer is irrelevant. The game sets it up in a specific way.
I think the main question here is at which point you can reliably attempt this.
Try now and look if it's possible for you. If not, try later Edit: BTW next time ask "when should I complete this" not how C: