Playing 1 on 1 games can be very useful, to develop your skill. You can practice standing in a line, getting creeps, and denying them. Also lobby 1 on 1 helps to solve conflict situations in the game, because going there on the same heroes, you can decide which of you is stronger. I propose to take a closer look at what it is and what it is for.

What is a 1 on 1 lobby for?

Tournaments are very often played in this mode, with Shadow Fiend as the main hero. His main ability is SHADOW RAZE, which hits the opponent with damage and can easily kill him. It is considered to be a skill matchup, and that's why it is used in games and tournaments.
Many other heroes are also used, such as Puck, Rubick, and the like. Everywhere the main goal is to prove that you are stronger than your opponent. 
Here also, with the help of a friend, you can test different chips against heroes. Test the initial purchases, and pumping skills. Try out different linups you're not sure about, or test a strategy against a hero you're having a hard time standing with. It can be useful to practice lashing at creeps. Ask to take a hero with strong attack damage, and take a weak one for yourself, and try to go after a line with a good networth. 

How to create a 1 on 1 lobby?

First you need to invite a friend to your team, then when you click on the "play" button, you will see a window where you can create a lobby. Click on it, and open the settings.
By clicking on the gear at the bottom you will see the detailed settings, which can be fully adjusted to yourself. We need 1 on 1 midu, so we select "ONLY MID" in game mode, choose a side and start.

Basic rules of 1 on 1 dueling

If you are playing classic zxc on Shadow Fiend, there is a set of rules to follow for a more fair and interesting game. Here are the main ones.

• The game lasts until the tavern is demolished, or the first death of one of the players;
• It is forbidden to farm the forest;
• It is forbidden to stop the first pack of creeps;
• You must pump souls on the first one;
• It is forbidden to pick up runes and buy botl, drops, sticks;
• It is forbidden to take off warlocks.