Custom Tournament" is a functionality that allows you to make your own personal tournament, including only players selected by you!
You can find this option in Belot games, when you enter the "Tournaments" section at the top you have two buttons "Standard" and "Custom".
When you press the "Custom" button, a page will open with the option to create an individual tournament. Also here you can see all the tournaments that have already been created or are already taking place.
On the Custom Tournaments page at the bottom you will have two options:
"Create a game" - from here you can create your own tournament, at which you will be the Host.
"Join" - here you will see a field where you can enter the code of an already created tournament room to which you have been invited.
To make your tournament, your profile must have reached level 10! When creating a tournament, you become its Host and you choose all the parameters according to which the tournament games will take place.