Future Bucks
Future bucks are a redundant money source.
Since every item on the crafting menu requires you to spend X amount of robot parts to build stuff and get to the next level, they don't want you to use up all your primary crafting currency on items you want more of.
So if you look closely, you'll see that every item has a "set". Cheaper items might be 4 before you complete a set and it switches over from robot parts to future bucks. This way you can save your robot parts to level up and get better prizes.
Hopefully that wasn't too confusing. :)
Since every item on the crafting menu requires you to spend X amount of robot parts to build stuff and get to the next level, they don't want you to use up all your primary crafting currency on items you want more of.
So if you look closely, you'll see that every item has a "set". Cheaper items might be 4 before you complete a set and it switches over from robot parts to future bucks. This way you can save your robot parts to level up and get better prizes.
Hopefully that wasn't too confusing. :)
