Even the arena?
Except the Arena, and the DLC, and the guild quests, and the expeditions.
I did a random 136 guild quest for a Deviljho yesterday. It was a rare quest, which means treasure area. So myself and one other ran to the treasure area, which for some bloody reason was all the way in the final area some 5 screens away from the start. And the apex Deviljho was at the start.
I don't know if the host was just stupid or what have you, but he seemed to not care about the treasure area and went straight to fight the Apex Deviljho with another idiot random. The two of us pinged a few times to get them to realize there's a treasure area but they didn't seem to care.
Then they died. Unsurprisingly.
Then they left the room, went back to the lobby and started flaming us. "I hate leeches like you" was my favorite. Leeches? I'm bloody 140HR, how would I get here by leeching off people? Since the two of us with brains were still in the actual fight, we couldn't actually explain anything so we just went to finish the 136 GQ Apex Deviljho ourselves. The fun part was that none of us could die, since the two morons wasted the lives already.
It was an epic fight. Took so frigging long with just two people and the map was so bloody huge. The Deviljho would run from one end to the other 5 screens away. I think after 15 minutes the idiot host finally left. Maybe he thought we were still AFK or something, I dunno. When we finally beat it it felt so glorious. I think my favorite parts would be when we would slowly approach the super Deviljho with our shields out and hunkering down to block the constant lasers. It was like two turtles vs a giant sea cucumber laser death machine with teeth. The fact that we couldn't screw up and die was probably the most exciting part, which is probably why it took so long as we were so cautious.