TL;DR at bottom
I'm a new player and the game is intimidating. I don't know why I thought it was a good idea, but I decided to go to the Imperial City because I saw the announcement about extra Tele Shard things. I had no idea what they were good for. Still don't. But double of any currency is probably worth my time. So yeah, I went there. Not right away of course, because it took lots of googling to figure out that the Imperial City is located in Cyrodiil which didn't help much because I had no idea where that was either. Boring story and many hours later, I'm finally in Imperial City playing Ebonheart which is very much my luck because I guess Ebonhearts suck at everything and everyone knows it, except me, because if I did know it I would have been like everyone else and picked a different faction.
But now I'm invested and lucky for me, I find a few other clueless people who also didn't get the memo about not playing Ebonheart in Cyrodiil. So our rag tag group tries to take a few flags because apparently that attracts more of the Shards or whatever. We take one and then get trampled by a sea of blue badges that filled up my entire screen. Not wanting to fatten the blue whale that killed us once already, we try our luck in the sewers. We painfully collect a few shards, and then someone suggest we kill Molag Bal.
I didn't know what a Molag Bal was but killing it had to be more fun than picking shards out of dead rats and feces, and I'm being told there's a chance you'll get some skin that turns you into a Daedra zombie or something. So we head to the center which ended up being much further and more difficult to get to than I originally realized because who bothers looking at the map anyway. And also because Daedra don't outlaw steroids which leads to super omega powerful Daedra that get their jolly's by slowly trudging through the sewers with that slow serial-killer-pace from the cliche horror movies. We ran into these guys more than we should have and I don't know why we thought we could kill Molag Bal if his henchmen were killing us, but its obvious I didn't give any of this much thought from the beginning when I hit "purchase" on steam.
So here we are, finally at the center, and since my luck only likes to only be accompanied by the word "***", there were of course 20 or more players from one of the enemy factions already there blasting through Molag Bal like a soggy sneeze through one-ply tissues. Before we knew it, we were surrounded by a hive of yellow, but unlike the ravenous whale up top, they didn't kill us right away, and we didn't bother attacking because even we knew there was no point. To our surprise they still didn't attack, and instead they moved to make a path through their cluster, leading up to the portals we needed to destroy in order to kill Molag Bal. It was like the golden gates themselves had finally opened to allow us passage.
They stayed back and even helped us pick off some of the Daedra. After we killed Molag Bal, the yellow went back to swarming around the portals that was it. They just let us go. So there is my very long winded story about how an enemy guild didn't kill us and instead helped us kill Molag Bal. I think they were called the Moonlight Hunters. It was probably the strangest encounter I've had in my month of playing, but it was also one of the most enjoyable.
TL;DR
I stupidly went to Imperial City after only playing the game for a few days and a huge enemy zerg helped us kill Molag Bal.