How do I get +10% Karma and 10% Experience Banner in GW2?

Check the Acquisition and "Sold by" sections, which list the vendors, containers, salvage sources and achievements that grant +10% Karma and 10% Experience Banner, where known.

What is the Trading Post price of +10% Karma and 10% Experience Banner?

The live buy and sell prices are shown at the top of the page, pulled from the official Guild Wars 2 Trading Post API.

Masterwork · Immediate

+10% Karma and 10% Experience Banner

Spawns a guild banner that will give +10% karma and +10% experience from kills for 30 minutes to any ally that touches it. Does not stack with other karma or experience banners.

Soulbound on AcquireVendor 25 copper

No crafting, acquisition, achievement or collection data is available for this item yet.

Item data from the official Guild Wars 2 API. Acquisition, salvage and collection data from the Guild Wars 2 Wiki.