Zarban

Old-school D&D suggesting rolling 1d6 every 30 minutes of exploration time, and on a 1, a random encounter occurs. You can also make extra rolls if the heroes make a bunch of noise or otherwise call attention to themselves. But there is a better way.

Goblin Punch has an interesting post on random encounters that introduces an “underclock”. This has a certain number of points that get reduced by a 1d6 every so often. When it’s down to zero, you get a random encounter. It’s slightly more complicated than that in order to introduce hints that a random monster is lurking, but that’s the heart of it.

I think this is a prime opportunity to use my dice timer mechanism. When you first roll (after 30 minutes of exploring), you roll a d20. Next time (every 10 minutes), it’s a d12; then d10, d8, d6, d4, & d3. If you roll a 1 at anytime, there’s an encounter. If there’s no encounter from the d3, it happens the time after that. This guarantees an encounter in no more than 8 opportunities, while–using the old-school method–it was very likely at some point after 6, but never guaranteed.

If you prefer that an encounter never be certain, you can just start keep rolling the d3. You could even walk the timer upward: from d3 to d4, d6, and so on–that’s the monster wandering further away.

Additional thoughts:

• When you’re rolling the d4 or d3, you should say the heroes hear weird noises, find monster droppings, etc., which gives them a bit of a warning.
• If they make noise or smells, make an extra roll with the current die.