Exchange your earned XP to POCOnce your attacks and defense are successful you will earn tXP. Ultimately this is the XP that can be exchanged for POC.The exchange rate between XP and POC varies from time to time. To know more about the XP rate, visit https://pocketarena.com/ and view the top right corner (Next to the website menu) to view the latest XP rate.
To put it in simple terms, XP earned in Castle Arena and other Casual Games has its use only in Castle Arena. XP that can be exchanged to POC is earned only by winning battles in Castle Arena.