Shops and trade¶

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There are two ways to get items from an NPC. A shop sells for gold and buys almost anything back. A trade is a barter: the NPC hands over one item for one of yours that is worth at least as much. Each is a data asset (a shop table or trade table) set on a placed NPC, opened by a node in that NPC's On Interact graph. Neither has any state of its own: stock never runs out, so the party bag and the party's gold are the only things that change. The idea that makes the rest make sense: every price comes from one number on the item, its Sell Value, and each system applies its own multiplier to it.

What you can change¶

A shopkeeper and what they sell: Open a shop.
A trader and what they offer: Set up a trade.
An item's price: its Sell Value (on the item), or Price Override on one row of a table.
The screens' wording and look: their Blueprints' class defaults (see Settings).

How it fits together¶

Piece	Kind	Job
`Shop/DA_XenoCore_Shop_Colony9`	Shop table (data asset)	The Gym sample shop's stock: seven pieces of equipment
`Shop/DA_XenoCore_Shop_KamosOutpost`	Shop table	The Gaur Plain shop at Kamos Outpost, which also sells rank I gems
`Trade/DA_XenoCore_Trade_Colony9`	Trade table (data asset)	The sample trader's offers and overtrade bonus
Open Shop	Blueprint node	Opens the shop, continues on Transacted or Nothing Changed
Open Trade	Blueprint node	Opens the barter screen, continues on Traded or Cancelled
`UserInterface/HUD/W_XenoCore_ShopScreen`	Screen	Buy / Sell / Quit, lists, quantity confirm, "equip now?"
`UserInterface/HUD/W_XenoCore_TradeScreen`	Screen	Their item, your item, confirm
`UserInterface/W_XenoCore_TradeRow`	Row widget	One list row on either screen
Shop and trade nodes	Blueprint nodes (XenoCore › Shop, XenoCore › Trade)	Prices, what may be bought, sold or offered, and the buy and sell actions

Both screens are pushed onto the menu layer, so the world pauses while they are open. The NPCs using the Colony 9 tables are placed in Maps/L_XenoCore_Gym; the Kamos Outpost shopkeeper is in Maps/L_XenoCore_GaurPlain.

Stock loads when the screen opens. Every Item in a shop or trade table (offers and the overtrade bonus) is a soft reference, so a placed shopkeeper does not load its stock, with its weapon meshes and abilities, along with the map. The shop and trade screens load the table's items as they open. See Loading and ticking.

Where gold lives. The party's gold is held by the progression component (Game/BP_XenoCore_Progression, on the player controller). See Progression.

Lifecycle¶

A shop¶

A shopkeeper talks first. There is no "Shop" verb on the prompt. The NPC's On Interact graph plays its dialogue, then checks Can Shop, and if the NPC has a Shop Table it runs Open Shop with Get Shop Table and the NPC itself:

The player chooses Buy, Sell or Quit.
Buy lists the table's items in tabs (equipment split by slot). Choosing one opens a quantity confirm showing the total and the player's gold. The most you can buy is the smallest of: what your gold covers, the room left under the item's Max Carried, and 99.
Buying takes the gold first, then adds the items. Anything that did not fit is refunded.
After buying equipment, the shop asks whether to equip it now, on a character you pick.
Sell lists your bag. Worn copies cannot be sold ("You cannot sell weapons that are in use"). Key items never appear.
The list stays open after each purchase or sale, with the numbers updated in place.
Leaving fires Transacted if anything was bought or sold, otherwise Nothing Changed.

A trade¶

A trader is any NPC with Trade Offers set. That adds a Trade verb on X to the prompt. The NPC's graph checks Is Trade Verb and runs Open Trade with Get Trade Offers:

The player picks what they want from the NPC's list first.
Then what they give from their own bag. Only Materials and Collectables can be offered.
The trade clears when the offered item's value is at least the wanted item's price. If it is also at least the price plus the table's bonus value, the NPC throws in the Overtrade Bonus item too, and the screen says so before you confirm.
One item for one item. The NPC never runs out; a second copy is a second trade.
Leaving fires Traded if at least one exchange happened, otherwise Cancelled.

Both nodes hide the interaction prompt and the dialogue box while the screen is up and restore them afterwards. Neither closes the conversation: the graph usually has a line to say after.

Prices¶

Price	Rule
Shop buy price	Sell Value × 10, or the row's Price Override
Shop sell price	Sell Value × 1, rounded down once
Trade value of Materials	Sell Value × 1
Trade value of everything else	Sell Value × 10
A trade row's price	the item's trade value, or the row's Price Override
The overtrade threshold	row price + the bonus item's trade value (or its Value Override)

Sell Value and Max Carried are on the item's XenoCoreFragment_ItemCategory fragment. See Items and inventory.

Materials cannot be bought from a shop, and Key items cannot be sold. The shop table's data validation refuses stocking either.

Rarity does not change any price. Xenoblade 3 makes value independent of rarity. The sort cycle (Y) adds Rarity, which lists the rarest first and then A–Z, beside Most Recent, Name and Value. Names are drawn in their rarity colour; see Set and style item rarity.

Trading at ten times a collectable's sell value is deliberate: it makes items picked up while exploring worth more in barter than in the shop.

The multipliers are fixed

The ×10 buy price, the ×1 and ×10 trade values and the 99-per-purchase limit are fixed in C++. To price one item differently, use Price Override on its row; to make a whole shop dearer or cheaper, a programmer has to change the multiplier.

Settings¶

Setting	Where it lives	What it does
Offers › Item	Shop table › XenoCore › Shop	An item the shop sells, in list order
Offers › Price Override	Shop table › XenoCore › Shop	Its price. 0 means "use the item's buy price", not free
Resolved Price	Shop table (read only)	The price that 0 resolves to, so you can see it
Offers › Item, Price Override	Trade table › XenoCore › Trade › Offers	An item the NPC will part with, and its price (0 = its trade value)
Resolved Price, Overtrade At	Trade table (read only)	The actual price, and what earns the bonus
Overtrade Bonus › Item	Trade table › XenoCore › Trade › Overtrade Bonus	The bonus item. Empty means this NPC never gives one
Overtrade Bonus › Value Override	same	Extra value needed on top of the price. 0 = the bonus item's own trade value
Shop Table, Trade Offers	Placed NPC › XenoCore › NPC	Which tables this NPC uses
Complete Heading	`W_XenoCore_TradeScreen` › XenoCore › Trade › Completion	The heading of the banner after a trade
Celebrate On Trade	same	Confetti and fanfare after a trade. Off by default
Tab Button Class, Row Class, Stat Row Class, Icon Set, icon sizes	Both screens › XenoCore › Merchant	Which widgets and icons the lists use
Texts under XenoCore › Shop › Text	`W_XenoCore_ShopScreen`	The shop's panel wording

Set Shop Table and Trade Offers on the placed NPC, never on the Blueprint

Set on B_XenoCore_Npc's class defaults, every NPC in the game becomes a shopkeeper or a trader, including your quest givers. These are per-instance settings.

Fails silently: an item with no category fragment

An item without a XenoCoreFragment_ItemCategory, or with Sell Value 0, has no price. In a shop it cannot be bought; in a trade table it is priced 0 and trades for anything. Right-click your tables in the Content Browser and choose Asset Actions › Validate Assets: both report such rows as errors.

Price Override 0 means derive, never free

There is no way to give an item away through a shop or a trade. A gift belongs in a quest reward.

Extending it¶

A new shop or trader: duplicate the sample table into Content/MyGame/, change its rows, and set it on a placed NPC. See Open a shop and Set up a trade.
Different wording after a shop or trade: add Show Dialogue nodes on the node's output pins in the NPC's graph.
Stock that changes over time is a different table swapped in by your own logic (for example on quest state, through Get Party Quests). Tables have no stock count or conditions.
Skill bonuses to prices and a third screen of this kind (a crafting bench, say) need a programmer; see the note below.

Never edit the sample tables in place if you want to keep them as reference; they are overwritten by template updates.

For programmers: classes and extension points

Tables are UXenoCoreShopTable and UXenoCoreTradeTable; the nodes are the latent actions UXenoCoreOpenShop and UXenoCoreOpenTrade; the screens derive from UXenoCoreShopScreenBase / UXenoCoreTradeScreenBase, both on UXenoCoreMerchantScreenBase, with rows on UXenoCoreTradeRowBase. Prices are in UXenoCoreShopStatics and UXenoCoreTradeStatics (BuyMultiplier, MaterialMultiplier, StandardMultiplier, MaxPerTransaction). GetSellPriceMultiplier and GetOfferValueMultiplier are the single place a skill bonus would go; both return 1.0 today. A third merchant-style screen derives from UXenoCoreMerchantScreenBase, which supplies the Menu input mode, back handling, the finish callback, rows, tabs, focus restore and the details card.

Why it's built this way¶

For programmers

One base for the shared mechanics. The trade screen came first; the shop is the second screen of the kind, which is the point at which the shared parts moved into a base. Neither child duplicates the focus, tab and pooling fixes.
One number per item. Baking a multiplier into the item would be wrong for the other two consumers, so the item carries Sell Value and each system applies its own rule.
One resolver per price. Rows, the confirm total and the actual transaction all read the same GetPrice, so nothing can be shown at one price and charged at another. The read-only Resolved Price fields in the editor are a display of that same function.
Every bag change goes through UXenoCoreInventoryStatics, and every gold change through the progression component, so the change messages fire and open screens stay current. See Events you can listen to.
The finish pin always fires. The NPC graph is suspended on the node. If the screen were torn down without answering, the conversation could never finish, so the answer is delivered when the screen deactivates, however that happens.
CommonUI reuses screens. CommonUI's layer pools activatable widgets, so the same shop or trade screen instance is shown again on the next visit. Anything that must be fresh per visit is reset in BeginShowing, which a child's show function must call first. A latch set once at construction survives into the next visit and, for example, stops the finish callback from ever firing a second time.

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