not bad but I think you should add these upgrades:
baking cooldown: base = 1 cake / 2 seconds - base price = 15
income: base = 1$ / 1 cake - base price = 100 (unlock at level 2)
NOTE: you earn 1 xp for every cake you bake. Base level 1 is 100, and multiplies by 2 every level.
xp gain: 1 xp / 1 cake - base price = $200 (unlock at level 3)
rare cake possibility: rare cakes are worth 10x the amount of a normal cake. base = 0.5% chance of rare cake - base price = $1,000 (unlock at level 5)
Rebirth: to rebirth you need at least $10,000,000 and level 30 to rebirth. this will give you rebirth points, but will reset your cash and upgrades. every time you rebirth, the requirements for cash will multiply by 5 and the level requirement will add 10.
Rebirth tree: you can use rebirth points to spend on upgrades on the rebirth tree. these upgrades include:
cash income. xp income, rare cake luck, rp income, upgrade cost
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