Them Bones of Adventure - VIII: Chases

Continuing my exposition on table procedures for common exploration feats & rules, which began here with part one.

Introduction

Now for chases, prelude or blood-pumping alternative to fighting. The DMG offers a couple of example tables for chases. It so happens that the system’s both mechanically lackluster and a gaping sinkhole of prep, so no. What I need is a good universal mechanic, I’ll worry with a chase’s particulars pending its context. 

I found it interesting (and problematic) how the system forced me to separately account for both the distinct stat of movement speed and sometimes-contrasting ability scores, namely Dexterity, ultimately leading me to decide to integrate both stats under a single mechanic.

The Crunchy Bits

Step zero is determining if a chase is actually what is going to take place and not a turtle and hare situation. Vastly differing speeds can be flatly denied the chance: there’s just no way you’re escaping on foot from a flying monstrosity on an exposed tract of moorland, but if what’s at stake is seeing if you can just reach that tree line over there in time…

As well it is important to establish both a beginning and an end condition to a chase, impeding iterative and redundant chase behaviour from PC and NPC alike and ushering a resolution.

Breaking Away from Melee

Discounting special circumstances, a character that attempts to break away will be exposed to a round of opportunity attacks to the rear (read: with Advantage) from the opposition on the round he decides to turn tail and go seek the better part of valour.

- While Disengaging and Moving are good enough for a fighting retreat, a proper escape requires a Dash and can’t be initiated if a character is hit by a melee attack, opportunity or otherwise, unless he passes a [Dexterity Save (DC = higher of 10 or Damage Taken)].

- Likewise, if struck by a missile weapon during a chase, a character must make a [Constitution Save (DC = higher of 10 or Damage Taken)] or lose half his progress for the round.

- If the attempt to break away is successful, the character will now be running away, a first roll dictating the starting distance away from the opposition who may then attempt pursuit, turning the situation into a chase.

The Thrill of the Chase

1. Define the type of chase – the key to the nature of a chase is its context and from there to one of the three physical stats, naturally aided by training in athletics:

- Short, sudden burst-speed chases in crowded and obstacle-rich contexts, such as in an urban environment rely on Dexterity. Mid-distance, even-grounded athletic chases, free of obstacles, are a contest of Strength, both are measured in feet and take at most a couple of in-game minutes to resolve.

- Protracted chases such as made overland by parties spread far apart but within visual contact or being followed through tracking end up subsuming the above considerations of who moves slightly faster than whom and resolve into a slog, represented best by Constitution as what counts in the end is the stamina to endure the chase and distance is gained or lost by how much time is spent recovering and catching breath and not so much on how hard a party pushes itself at a given moment.

The shorter chases, being quick to decide, won’t usually offer a great deal of options. If within a dungeon or other constrained environment, I’ll describe everything only in the broadest strokes and try to keep in mind that space is usually very limited and time is of the essence. Protracted instances on the other hand can be much more rich and fluid in terms of choice, as this kind of chase tipically lasts from several minutes to hours (even days, depending on how open the terrain happens to be and how easy to track the quarry is) and the progress will be measured accordingly (Hundreds of meters and Kms or yards and miles for imperial scum).

2. Adjudicate how far apart the two entities begin. This will be a dynamic total, adjusted as the chase unfolds and distance is gained or lost. If the distance between participants was not set in stone prior to the chase’s commencement, it will be now.

Keeping unified track of everyone will require a dice array or a diagram on a sheet of graph paper, it being important to emphasize both the evolving distance between the two parties and how much ground the chase itself covers. I’ll default to applying the “each square = 5 feet” scale, as yet unsure if it’ll hold properly to ensure the desired effect.

3. Roll as needed until resolution is reached:

Short Chases

- Extended check of [Movement Speed + Rolled Dexterity/Strength (+ Athletics proficiency die)], contested by the opposition.

- A character who doesn’t devote his full concentration to running, with the player dithering, asking questions or taking some other action will lose half his movement for the round.

- Fumbling means the character was faced with a context-appropriate obstacle and must roll to save or lose his round of movement.

Each character’s movement in a round is thus a number of feet resulting from the summed total of the character’s speed with the rolled attribute, modified by the proficiency die if trained in athletics. I choose to use the proficiency die here to lend a bit more weight to athletics training than just the flat “+2”, which would otherwise be of too little consequence in a typical 40’+ total.

Protracted Chases

Accounting for scale and the fact that a group moves roughly at the speed of its slowest element, differences in movement speed between parties will get shrunk into irrelevance unless they’re noticeable (difference in speed of 10’+) and shared by all the members of a group, in which case an adjunct roll of d4 to d8 can be added to the main check. Overland progress will depend on how close the chase is taking place with the time-compression deriving from that, which can range from something like “furlongs of progress/hourly roll” to “miles of progress/daily roll”.

- Extended and contested single group roll of [Constitution] as the party is being pursued for hours over a long distance with visual contact (possible on a desert or mountainside chase) or tracked over several days through the snow.

- A unified group roll is a single d20 roll made with the worst modifier available in the party, this roll does not count as being made by any particular character and is not subject to effects that do not extend to the whole of the party.

Harsh? Yes, a bit. But I prefer fresh-faced harshness to the illogical incoherence (not to mention statistical trap) of collective rolls as prescribed by the PHB, that reads that “the stronger characters help cover for the weaker ones” in some way that until today utterly escapes my reckoning.

Mounted Chases and others

Mounted or vehicle chases will use the mount's Speed but rely on the rider's Dexterity, with the roll's total capped by the mount's own Dexterity or Strength if we're talking a ponderous type of beast.

Climbing, Swimming or Rowing chases will be the province of Strength.

Even erring on the side of generosity with the game’s assumption of average competence level for all characters (i.e. all characters are old-school fighters and then have some additional capabilities slapped on top), more specialized means of transportation will forcibly require training in the relevant skill (Athletics or Animal Handling) or some other background-specific means of determining aptitude at a given challenge or the roll be made at Disadvantage.

Escape…

For short chases, upon fulfilling one of these conditions, the fleeing party will have escaped:

- Reaching a predetermined distance to shelter.

- Putting such a distance from pursuers as to be able to effortlessly hide, this distance varying in an inverse proportion to the amount of sight-obscuring features:

- City, heavily wooded tract: twice the pursuers’ running distance

- Town, mildly wooded grounds: three times the pursuers’ running distance

- Hills, light woods, rocky outcrops: five times the pursuers’ running distance

The examples above rely on heavy abstraction, being subject to be superseded in play by a better defined lay of the land. A typical example being the dungeon, a place concrete to the point of being mapable and where thorough searches are much more likely to occur and be successful, no matter the distance.

- Attempting to hide even if not conforming to anything approaching the above might still be possible, but it will require rolls.

- The pursuers, if unintelligent, becoming distracted or disinterested. For this I thank 5th edition’s exhaustive stat-blocking, for it will be decided by a Wisdom check.

- The pursuers becoming discouraged by a difficult to traverse hazard (again, WIS or relevant check, no DM fiat).

- The pursuers becoming tired of the chase. Here’s a placeholder for the link to where I’ll dwell further on this.

Long chases will by necessity have to be treated in a more case-specific fashion, though tiredness will always definitely apply.

Closing Thoughts – Cutting Loose

On short chases, a party on the run will naturally get spread apart due to the differing movement and progress rates, the distance between parties being measured from the front chaser to the tailing element of the quarry.

If dealing with groups of characters, the unified party roll represents the fastest of the chasers and the slowest element of the quarry, depending on the roller’s role in the chase, the remaining individuals of each group, if any, being presumed to be in close proximity.

I’m thinking, if a group expresses the desire to, it could ponder cutting loose a lead-footed element, the party choosing to abandon the man who drags his feet to his luck rather than face the consequences, making for some good drama if we’re talking henchmen or – Gods forbid – PCs. This would net the party a better modifier, signifying the party’s timely letting go of someone who is struggling to keep up or unable to continue altogether and is dragging the group down.

What this (or these) disavowed element might then do is up for guessing. Attempt a splinter chase, try to hide or even stage a noble time-buying sacrifice, all are within the realm of possibility. I get that this is controversial and not something that I’d enforce or encourage, just entertaining the thought.