Products and credits

Fourteen developer products, live prices, banked purchases and sharing ProcessReceipt.

Fourteen products

Two per troll: one for the single target button, one for the everyone button.

OneProductId = 3707848824,
AllProductId = 3707849001,

A product id of 0 hides that button. A troll with Enabled = false hides both.

Prices are never in config

There is no price field anywhere in this system, deliberately. A number written in a config file goes stale the first time you change the price on the website, and then the button lies to your players.

Instead the button asks Roblox for the current price and shows that.

Format = utf8.char(0xE002) .. "%d",

%d is the price in Robux. utf8.char(0xE002) is the Robux symbol: Roblox's own fonts draw that code point as the icon, and it is written this way rather than pasted in so the config file stays plain ASCII.

Drop it for a bare number.

Credits

Free = "FREE (%d)",

A player can end up owning a paid troll they have not used. The button then reads FREE with a count, and pressing it spends the credit instead of opening a purchase prompt.

Credits happen when:

Situation
The target left before the receipt arrived	The buyer is told privately, and the go is banked
The target became immune	Same
No target was selected	Same
The receipt arrived with no recorded intent	The go is banked

That last one is the important safety net: if a player buys a troll and their client forgets which target it was for, perhaps because they rejoined between paying and the receipt landing, they get a credit rather than nothing.

Credits are saved with the player's profile

They persist across sessions, so a purchase made just before a disconnect is still waiting when the player comes back.

Credits are per troll and per scope, so a banked Kill on one target does not become a banked Kill on everybody.

Duplicate receipts

Roblox can deliver the same receipt more than once. The system records the last fifty purchase ids on the player's profile and grants each one only once.

The guard needs a working profile

If the profile service is unavailable, a warning is logged and duplicate protection is off: a receipt Roblox delivers twice would be granted twice.

That is a startup problem rather than a normal condition, but the warning in Output is worth paying attention to.

ManageProcessReceipt = true,

Roblox allows exactly one ProcessReceipt callback per game. Whichever script sets it last wins, and every other product in your game stops working.

If this is the only thing selling products, leave it on.

If you sell anything else, set it to false and call the handler from your own:

local PurchaseService = -- the system's PurchaseService

MarketplaceService.ProcessReceipt = function(receiptInfo)
    local decision = PurchaseService:HandleReceipt(receiptInfo)
    if decision ~= Enum.ProductPurchaseDecision.NotProcessedYet then
        return decision
    end

    -- your own products here

    return Enum.ProductPurchaseDecision.NotProcessedYet
end

HandleReceipt returns NotProcessedYet for anything that is not one of this system's products, which is your signal to carry on.

What a failed grant means

Return	Meaning
`PurchaseGranted`	The troll landed, or was banked as a credit
`NotProcessedYet`	Nothing happened yet. Roblox will retry

An everyone troll that reached nobody returns NotProcessedYet, so the purchase is retried rather than lost. Returning PurchaseGranted for a troll that did nothing would be taking money for nothing.

Pricing advice

The two scopes are very different products and should not be priced the same.

Button	Suggestion
One target	Cheap enough to be an impulse. This is your volume
Everyone	Several times the single price. This is your event

Kick on the everyone button empties your server, so either price it as the most expensive thing you sell or leave its AllProductId at 0.

The server cooldown limits how often everyone trolls can fire regardless of price, so pricing and AllCooldown work together. See Targeting and immunity.

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