Please add 2HG

[Snaht]

This game is pretty stale as a 1v1 game. Is it possible to add a two-headed giant game mode a 2v2?

[Bizeboy]

They are going to have to but do you think the algorithm can rig 4 decks against each other? i dont think the code can handle it

[Teric]

Hasbro CEO mentioned investing in the longterm for Arena earlier this year, and specifically mentioned Commander in that.
The obvious issue is that the Arena engine just isnt currently made for that. Would likely need a massive redesign from the ground up to support it. The game already has a function to kill games for being too resource costly, I don't think it would like a larger format in it's current stage. Quote from WotC_Jay on reddit:
"With multiplicative effects, the counts of these can get quite high, forcing us to take down that game (lest that game take down others). This is something we've been spending a lot of time on tracking, understanding, and improving."

My big worry with any of those larger formats like 2HG or EDH is obvious. I Do Not trust this playerbase to play responsibly. I think the only reason MTGO isn't a hellscape to play is the games paywall making bad play less common. And the Xmage and Cockatrice communities have enough communication to block it out themselves. But on Arena, unless they decide to nut up and let us actually talk to eachother, I can see it getting out of hand very quickly.
People already complain plenty about roping in 1v1s, now throw in 2 extra players. People forgetting to pass priority, or just straight murdering a single person before conceding because they don't care. It's just grounds for terrible things. All the tiny things that can be minor annoyances in 1v1s, piling up exponentially. And of course, no social responsibility.

Bonus Issue: Mobile. I honestly cannot imagine how a 4 player board would work on a phone. Assuming it doesn't just crash the client, it would be visual overload.