Golden Scrap

Golden Scrap (abbreviated GS) is the third currency you'll get in the game. You'll get your first GS when you

get 100 million Scrap. You need to restart (Prestige) your game, and you'll lose all your Barrels and Scrap but you'll keep everything else.

Production Boost
Each GS will give you +1% to your Scrap production (up to 51%), meaning it allows you to go further than before.

Needed for Stars
You'll need to get GS to get Stars. If you haven't got 10 Stars yet, get a Star as soon as you have enough GS.

If you've got 10 Stars and above, try to don't be low on GS, as you'll need its bonus.

Optimal GS gathering
Don't go very far, especially under 6 Stars, because you won't have Golden Scrap Multipliers.

If you're at 5 Stars or more, the best is to upgrade 'Better Barrels' from Scrap Upgrades for bout 10 seconds, then restart and repeat.