Random Encounters: Post-Apocalyptic Ruined Building

This week I realized that I've left some important RPG genres out of my Random Encounters posts. So before I start cycling back through the genres with new locations, I want to hit up those remaining big genres, starting with today's: post-apocalypse.

Creature

1. Leather-and-steel clad raiders armed with spiked baseball bats and shotguns

2. A gigantic frog with acidic spit and/or mucus

3. A barely alive scavenger covered in bite marks

4. Radioactive mutant zombies!

5. An unhelpful maintenance robot

6. A large, black-feathered vulture with fire breath

Environment feature

1. A wall collapses onto the area.

2. Concrete rubble falls from the ceiling at random intervals.

3. Auto-turrets dot the walls and react to quick movements.

4. A pool of irradiated slime illuminates the area with a greenish glow.

5. Purple fungus growing in the area sends out psychic tendrils to manipulate the unwary.

6. A working juke box plays old music that echoes eeriely throughout the building.

Surprise

1. An old—but still fully functional—tank crashes through the wall.

2. A pack of mutant wolves comes around the corner.

3. All of the building's old electronics and lights suddenly flash on and start working.

4. The floor rumbles and then mechanically separates, revealing a hidden underground chamber.

5. Bounty hunters (or trophy hunters) arrive to capture or kill the creature.

6. A wave of poisonous gas rolls through the area coming from outside.