My Reavers on the Seas of Fate campaign is well underway and the PCs are all over the mean streets of Riddleport. There’s some common scenarios that come up in urban adventures that I wanted to streamline; here’s my current efforts for your edification and comment! They’re Pathfinder based but very easily adapted to anything d20-ish. First, we have chase rules!
Chase Rules
Exciting chase scenes, the staple of action movies everywhere, are very hard by default in D&D because though every other part of the rules has variance built in – from stats to skills to damage – movement has always been completely static. “30 feet a round whether you need it or not!”
I got Adamant Entertainment’s Tome of Secrets for Pathfinder when it came out, and it has chase rules, but those rules are like a lot of chase rules I’ve seen in RPGs over time – way too complicated. They’re 40 damn pages of specific maneuvers and all. The entire Combat chapter in the Pathfinder RPG is only 25 pages. I wanted something that could be run without everyone having to do homework; in my opinion if a new bolt-on special case ruleset is more than about 2 pages then “you’re doing it wrong.”
So here’s what I came up with. It was hard to balance it out but after a couple playtest chases in the real campaign I think they are pretty light and easy to use, fair, and keep the PCs engaged.
The Movement Check
A character’s Move check is +2 per 5′ of base speed. For an unencumbered human that moves 30′, that’s +12. In a self-powered race like a footrace, you can add your STR bonus to this in a given round but then have to make a DC 15 Fort save to not become fatigued from the exertion. Use this same formula for other movement types (riding, swimming) because it takes differing speeds into account well. (as a bonus, this means you can have a chase where various participants are using different modes of movement).
The Chase Track
Rather than keeping up with specific distances, a chase has distance represented by an arbitrary condition track. It’s defined relative to whoever’s in the lead, and has six levels –
- Close Contact – within melee range of leader. Subject to all obstacles the leader has to deal with.
- Point Blank – close range (all those “within 30 feet” powers proc here). Take leader’s obstacles or take an alternate path at DC 20.
- Short – Take leader’s obstacles or an alternate path at DC 15. -2 on ranged attacks.
- Medium – From this far back, it’s usually easy to avoid obstacles. -4 on ranged attacks.
- Long – -6 on ranged attacks.
- Lost – you done lost ’em. If you have allies still in the chase and you can still run (not fatigued or just giving up) you can run after them sufficiently to at least arrive on the scene once it’s all over, but you can’t get back into the actual chase.
For each 5 points by which you beat the leader’s movement check, you close by one category on the track; similarly you slip back by one for each 5 points by which you miss their check.
Chase participants start at a chase level that makes sense – if they are right there with the leader and take off after them when they take off, they can start at point blank. If they’re a round of movement away, or pause to shoot or take another action before they get going, start them at medium range.
Obstacles
In a chase, there’s a bunch of different kinds of obstacles and complications that can come up. Here’s a sample but not comprehensive list. In general the checks to pass these obstacles are DC 15. If you fail the check, you drop back one level on the chase track; if you miss by 5 you take 1d6 nonlethal damage from a collision or similar mishap. This is an urban specific list. In a crowded urban environment, each round has a 1 in 3 chance of bringing a mandatory obstacle, or the leader can deliberately head towards obstacles as desired. Roll 1d8 for what type, or choose one:
- Simple (Acrobatics, attack an object) – barrels, gate, street vendor’s blanket, etc.
- Barrier (Acrobatics) – fruit cart, unexpected turn
- Wall (Climb) – traditional “end of alley” wall, fence
- Gap (Acrobatics/Jump) – ditch, open manhole, pit
- Traffic (Acrobatics/Overrun) – pedestrians, mule team, orc pirates
- Squeeze (Escape Artist) – crawlspace, hole in wall
- Water (Swim) – river, wharf, pool, fountain
- Terrain (Acrobatics) – gravel, mud bank, slick cobblestones
Chase participants farther back on the chase track can choose whether or not to hit the same obstacle. Chasers in close contact have to negotiate the same obstacles as the leader. Chasers in point blank can take the obstacle or make an alternate check at DC 20 to avoid it – for example, “I can’t swim, I’m going to run around the reflecting pool instead.” Chasers at short range can take the obstacle or an alternate check at DC 15. Chasers farther back can generally avoid routine obstacles, but the DM can require them if it’s logically necessary (the leader swam across the river, for example).
You’d choose different obstacles and skills for other kinds of chase – a horseback chase would use Ride instead of Acrobatics, and a chase in the country would have trees and hedges instead of crates and alleys.
Actions
Anyone in close contact with the leader can conduct melee attacks on them. Whoever wins initiative gets to determine if attacks or Movement checks happen first.
A character can take a missile attack but automatically drops back one level on the chase track when they do.
If the chase goes a number of rounds equal to anyone’s CON score they have to make DC 20 Fort saves each round or become fatigued, and effectively drop out.
Chase Playtest
Our PCs ranged from halflings and humans in encumbering armor (Move +8) to barbarians and monks (Move +16).
In their first chase, they went after the Splithog Pauper, a skilled rogue. He had a normal Move (+12) but high Acrobatics, Climb, and Escape Artist checks.
The chase was pretty long. Everyone managed to stay in the chase; as the slower guys dropped back they benefitted from not having to negotiate as many obstacles. The Pauper wasn’t rolling well on his movement checks and deliberately hit a lot of obstacles to try to shake the faster guys – the barbarian stayed with him, but he managed to push the rest of them back with this tactic. The cleric was the only one with a ranged attack; he shot an icicle at him a couple times but to limited effect.
There was a cool obstacle moment that everyone thought was very “parkour,” where the Pauper ran and dash vaulted through a fruit stand; one PC followed through the gap with his own leap but the next didn’t quite make it and busted, spraying fruit everywhere. The barbarian caught up with him legitimately and was stabbing him with his boarding pike (after a pretty bad string of misses he finally was connecting); the cleric used an Infamy Point to find a shortcut to head him off and gave him a good clotheslining; at that point we dropped out of chase mode and the two PCs cut him down before he could maneuver away from them.
The next chase was interestingly different. This was the party trying to follow a guy through the tenements, but he spotted them and ran. He was just a level 1 expert, nothing special, but he rolled really well and lost most of the party except for the tracker (the rest of the party was staying an increment behind the tracker to avoid detection). But the fleeing guy totally sucked at obstacles, and after a couple slowed him, the tracker got into close contact and dragged him to the ground for a good cuffing and stuffing.
In the end these rules rewarded faster Speeds and higher relevant skills without being overwhelming – in an earlier draft I was using the Acrobatics skill as the Movement check but it made that skill too much of a “whoever has it wins and whoever doesn’t loses” power. The quarries had a good chance to get away in both situations but after a good hard run they got them. The chases were long enough they were interesting but went quickly enough and were dynamic enough that they held interest.
These rules work well for a “one on many” chase; it’s not clear how they’d work for a complex many-on-many chase (e.g. horde of zombies vs. party of PCs).
Geek Related 
