Hello, you included in your bundle of 13 packs bundle this megapack which contains 10 of the 13 packs...
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Edit: Hello again! itch.io provides developers with the option to set a custom price for buy all. As buy all does not allow us to exclude individual packs, the buy all option inevitably includes our Megapack, as well as the individual packs included in the Megapack (along with our three most recent individual packs).
The overall price to purchase our Megapack along with our three most recent packs is $45, which is reflected in the custom price we have set for the buy all option. Happy New Year!