Videogame-style shootout between two teams of... chickens?
The battlefield was a dream-distorted version of my old (IRL) house, where we used to keep a bunch of chickens.
The HUD was seemingly based off of GTA Online, with the same weapon wheel and what-not. At first the combatants weren't actually chickens, just normal human characters. I have no idea what sparked the battle, perhaps it was actually a videogame in my dream.
I was doing fairly badly at first, then at one moment when a few of each team were shooting at each other I ducked into cover, switched from the shotgun to a marksman rifle, then popped out and managed to kill two or three of them with headshots. It was around this time that everyone on both teams turned into chickens, I think. Or maybe it was just my team...
The building where my house was IRL seemed to be some sort of bar/saloon which may-or-may-not have looked similar from the outside.
During a lull in fighting, I crept inside and up some stairs towards the bar, wondering if any enemies were in here as well. It was some rough-and-tumble sort of place, although I think I was the only patron at the time, I went up some dimly-lit stairs and reached the bar, and the lady behind the bar told me something about a display through a door to my left, where they'd preserved part of the place how it was in the good old days when it was really crazy.
So I went through this door to have a look, pushing it cautiously open with my gun hand, ducking my head to make myself a smaller target in case any hostiles were watching. I stepped out onto an enclosed verandah packed with tables and booths, all very battered and messy, with a knife stabbed into a tabletop and everything kept as though a brawl had taken place.
Through the windows lining the walls I could see the yard on three sides, and my team of heavily-armed chickens standing guard on our side. I think this is about when I woke up.