Because all auctions work with ethereum blochchain. If you create BTC or XRP Drawing, money will still be received through the eth, and the winner will receive bitcoin or xrp - and the one who played bitcoin - will receive the ethereum GOAL
Where can I read this information in more detail?
this is elemental. you can find all the information you need on the official website of the project. There is also a white paper, which contains all the documents related to the project and participation in it. all the elements and details are there. be careful and follow it.
I am not sure that here is a white paper as long as there is no ICO, so instead of WP there should be an instruction with all explanations,that's how it works