You are very welcome to test Rebirth now if you wish. But please make a backup of your save game first, and verify it works.
Press shift-R to enable Rebirth, it is disabled by default. You can test if it works, but since you already have many monster credits you can probably just buy all three upgrades at once.
Great news it is ^^ thanks, both!
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Exported my save (4 diams so far) > ReBirth (=RB)
>initial passive income=.3/s
Spent 4 diams on *2 (1 diam) and *2 (3 diam), for *2*2=*4
expecting a 1.2/s passive income
> actual passive income=.8/s
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Is there anything I missed or is it just because RB hasn't been fully implemented yet?
Sorry for the newb questions, it's the first time I actually ask questions about the process of building a game. Don't hesitate to tell me if it's not welcome.
The questions are a great help so just keep them coming. Each diamond (before you spend it) gives a +10 % income bonus. So 3 diamonds would have given you +30%. Then you spend them to get 4X, but you also lose the 30%. That is probably the reason. The +10% are just a bonus if you have some spare diamonds.