Its tough for matchmaking
How do I play with my friends?
Hey, you will need to create a 'Group' to play with your friends in MatchMaking battles on the HTML5 version (Browser/Client) of the game.
Creating a 'Group' in that version has been demonstrated and explained clearly in this article, please have a look. It has also been explained in the solution to this topic. :)
Customer support service by UserEcho