OP, you went online and trolled your boyfriend successfully. This is really sad that you're reacting like this.
I think you were in the wrong to even engage in this exercise. You went online specifically to mess with him. And when he didn't realize it was you, you decided not to tell him, continuing the lie. You have no idea what the subculture is like where you were. You don't speak the language. To me, it sounds like you were hardcore trolling him and you had no idea. When people get trolled, they feel like they have to defend themselves.
You pretended to be someone else and pushed buttons, unknowingly, for a significant amount of time. You could HEAR that he was angry, and you kept going. That's actually kind of fucked up. Like not even a, "Hey man, it's me. Relax." Like, you were so disgusted and put off that you wanted him to keep being angry? Were you afraid? You were pushing his buttons dude.
And now you're upset because he lashed out in defense?
His reaction doesn't have anything to do with anything outside of the game. You don't speak the language where he was. You don't understand the culture. You trolled him.
And you haven't talked to him about it? You're just going to stay the night somewhere else? Presumably he's been a good partner. You live together. But he gets nothing after one instance where you pushed his buttons as someone else...? Cmon man. What the hell. So now, not only did you lie to him and engage in deceit, but you're just going to go and be upset somewhere and not even communicate with him why that is. Does this guy ever yell at you? Does he ever get out of line? If he's scary outside of the game, yea man, totally go. If this has been a regular relationship, I think you're being kind of whack here. It's too bad only three other people in this thread understand that subculture. You got a total echo chamber. I seriously hope you think about what you did objectively, because you lied to this dude and pushed his buttons and now you won't tell him why you're upset. That's totally whack.