When we say proof of reserves, we are specifically referring to those assets we hold in custody for our users. This means we are showing proof that OX.FUN has funds covering all of our users' assets 1:1, plus some reserves.
When a user deposits one Bitcoin, OX.FUN's reserves increase by at least one Bitcoin to ensure that customer funds are fully backed. This proves that OX.FUN holds all user assets (plus some reserves) at a 1:1 ratio.