I use the same rules for random encounters regardless of what game I play, but have some added house rules here for DCC RPG that I will include for posterity. Most of these rules never come up at the table, and are mostly just internal guidelines I use when running the game.
Time Keeping in DCC RPG
- One round of combat is 10 seconds.
- One turn, is six rounds, or 1 minute.
- A random encounter is checked every 10 minutes (Mostly).
- Main hallways are checked more frequently (5-8 minutes).
- Extents of large dungeons are checked less frequently (15-20 minutes).
- Searching a 10 foot section of wall for secret doors or the like, takes 2 minutes.
- Searching a rooms contents takes between 2 and five minutes, depending.
- While not fighting or fast walking, real time equals dungeon time.
- After a fight, characters take a turn to drink some water, bandage wounds, etc.
- Moving down hallways takes real time, or 1 minute per short section if actively searching for danger.
- After an hour of play, torches need to be replaced (I need to remember to enforce this more often).
Checking for Encounters
I use a very simple system for checking for encounters. I roll a 1d6. On a 1-2 (33% chance) there is a wandering encounter. On a six, (16% chance) There is a special chart I use that includes: Random sounds in the distance, clues left on the ground, rubble or fecal material, tracks, etc.
Creating the Encounter Table
When creating the random encounter table for an area, I first look at what sort of things might be wandering the halls. This helps me not only have reasonable encounters, but can give the players clues to what else might be lingering the area they haven't encountered yet. I will usually use a percentile die, and assign creatures based on how big their community is in the area, and how mobile they are. I will also include a few listings from areas a bit further away, and then throw in a few dungeon classics like oozes. I will have a few wild cards from deeper in the dungeon, but usually only near the main passages or in an area containing a passageway that leads deeper.
Creating the Random Events Table
Think of sounds the characters might hear based on the area they are in. If there are doors that need to be opened to get around, make sure you have the sounds of doors slamming, creaking of wood or the grinding of stone in the distance. Screams, sounds of combat, and strange babbling can all add the theme and mood you want to portray in the underworld of a dungeon. In nature settings this gets even easier to come up with, and can lead to a very immersive experience. This table can also be an excellent place to stick the weird stuff you would like to include in the dungeon. In my megadungeon I have a few magical events that are triggered by this table.