Users bring foreign assets via XCM. The assets are expected to live in pallet-assets (or something else that also implements Inspect + Transfer from frame_support::traits::fungibles).
A deposit is required for the challenger to create a match.
An equal deposit is required for the opponent to join the match.
pallet-assets
(or something else that also implementsInspect
+Transfer
fromframe_support::traits::fungibles
).