I just had a complete conversation via the in-game emotes

I had played Luke Cage on T2 and nothing on T3.

T4, my opponent played Darkhawk into that gawd-awful Quantum Realm. I played two cards into it - Zero followed by She-Hulk. The turn resolved, I was winning the lane by two points.

He emotes "What just happened?!"

I normally ignore emotes like that but I realized he might legitimately not know, so I gave my Luke Cage a happy face. (Luke keeps the Realm from lowering the stats.)

He frowny-faced it, then fist bumped me. I fist bumped him, and he retreated.

It just made me laugh that we achieved actual communication using a handful of emotes.