Another bit of advice that I find particularly useful from Sly Flourish is to add three features to a fantastic location for players to interact with (see “What are three fantastic features of this location?” in Creative Mind Exercises for D&D). For a recent delve into a mine, for my 5e campaign, my three were a rusted minecart, rail track, and a trellis bridge over a deep chasm.
I didn’t create any rules for minecarts, nor do I think you should. Instead, improvise rules for features using your RPG system’s mechanics. For instance:
- The artificer took a turn to oil the wheels of the minecart, which I ruled he automatically succeeded at. (Where’s the fun in a minecart that doesn’t move?!)
- When players decided to get in and later get out of the minecart, I ruled they had half their movement range on a turn when they did that.
- The track sloped down, so when players entered or exited the cart, then the player at the front of the minecart had to make a strength DC check (which increased as more players entered, from 15 to 18).
- The minecart became portable cover for ranged attacks against troglodytes entering the mine. Treated as regular cover. (The wizard minor-illusioned a cover over the cart!)
- When one of the players hopped out, the cart started to move, so another player slammed his foot on a brake outside the minecart (which I had never described, but the players assumed would be there, so there it was). I decided on the fly that the brake was rusty and that I’d reverse the strength check for the fun of it – a high roll would break the brake; he rolled a 3, so I ruled he engaged the brake successfully.
- The half-orc missed the players talking about the narrow bridge over the chasm and decided to shoot the cart over the chasm – she failed a dexterity check (on trying to push the cart a certain way) and ended up going on a roller coaster ride! Fortunately for her, the dwarves had engineered the track to incline back up (improvised at the table) and come to a gentle stop outside the new shafts the dwarves had been digging before abandoning the mine.
Now “low prep” doesn’t mean “no prep” – you should prep what you enjoy prepping and what you find hard to improvise at the table. Keeping in mind that players are by their nature unpredictable.
In this case, my players had already had a session in this mine system and had found the loot while purposefully avoiding the dragon they had all told me back in Session 0 they wanted to fight. The troglodytes were just supposed to provide a strong start to the session – I expected the players to use the minecart to escape from the troglodytes and find another way out. Instead, of course, the strong “start” became almost the entire session as they magicked, battled, and then drove away the dozen troglodytes.
Sketching out rule subsystems for each feature of a fantastic location, such as the minecart, would have just been too much prep, in my case. And had I done it they would have probably spent all their time crawling along the trellis instead!