D&D 5E Chase Rules - help checking the maths

[TaranTheWanderer]

I'm working up some Chase rules and slowly fleshing them out. I'd like some help with DCs and stuff, as well as anything I may have overlooked. And General comments to hammer out kinks. I'm trying to cover many bases. Lots of people have skills and talents and abilities that should help with a Chase.

How to win:
1. DM chooses a number of rolls. 2-3 for a short chase, 3-4 for a medium, 5-6 for a long. (or whatever.) Whoever gets the most successes Wins.

Base skill is (STR) Athletics

2. Choose the DC(I want to add/tweak these. Suggestions welcome):
DC is based on terrain.
DC 8 Open Field/Clear Street with few obstacles: 8
DC 10 Crowded Street/ Light Brush
DC 12 Hilly or scrub or muddy, deep sand:
DC 15 Forest or Mountainous:

3. Calculate your total bonus: Athletics +

These skills will modify Athletics rolls for the Pursuer:
+2 Proficiency Acrobatics: jumping over and around obstacles
+2 Proficiency Perception: Making sure you can see or hear where they are going

These skills will modify the rolls for the Pursued:
+2 Proficiency Acrobatics: jumping over and around obstacles
+2 Proficiency Stealth: Someone dodges behind obstacles to try to lose their pursuer

Abilities
Base Movement Is 30 feet:
+1 for every 10 feet faster than 30 feet
-1 for every 5 feet slower than 30 feet

+4 Expertise: double any bonus for a relevant proficiency
+2 Cunning Action:
??? +2 ?? Reliable Talent: I'm worried having reliable talent athletics would auto-win any chase...
+1 to +4 Misc: A player might Bring up something that's relevant. A GM is welcome to give a +1 to +4. Example: Warlock can cast disguise self at will. A chase through a crowded street, the GM might award a +2 to the warlock's rolls as he constantly is changing disguises to lose the pursuer.
Tabaxi movement ability = auto extra success on first roll

4. Roll Athletics against the DC.
You gain 1 success for meeting the DC and 1 additional success for every 5 points above the DC and failures subtract from successes.
example: DC: 10. An athletics roll of 20 would net you 3 successes.

Other:
Constitution: You can make a number of checks without penalty equal to your Con Bonus. After wards you suffer a -1 accumulating penalty each roll
Example: CON 14. 5 roll Chase. The first two rolls have no penalty. 3rd roll -1 penalty; 4th roll-2; 5th roll -3

EXAMPLE:
Rob the Rogue is running away from Bob the Barbarian.

Rob is a stout halfling with 25 movement (-1); has a Con of 14 and a Strength of 10; Proficiency in acrobatics (+2)and Expertise in Stealth(+4); he has cunning action(+2).
Rob's total Athletics roll is: +7

Bob is a human with 40 foot movement (+1); Has a Con of 16 and a Strength of 16; He has Proficiency in Survival, Athletics and Perception (+2)
Bob's Athletics is +9 (+3 proficiency+STR+bonuses)

Bob is Chasing Rob through the Forest: DC 15. They will do 4 rolls.
In round 3, Rob will get a -1 Penalty
In round 4, Bob will get a -1 Penalty and Rob will get a -2 Penalty.

It's close, but the odds are stacked in Bob's Favour.

Optional Finish.
If Rob were to get some lucky rolls and win the race, there is a chance that - even though Bob lost him, he might still be able to track him.
Bob makes a Survival roll against the Forest DC 15 modified by Rob's Stealth and Survival (+2 for each one. Rob only has Stealth but it's expertise)
Bob has to make a Survival roll and beat a DC 19. If he succeeds, Bob finds a trail. While the pursuit is over, Bob has a method to eventually track down Rob.


I think that's everything. It's supposed to be detailed. my group likes that so I don't feel it's too overly-complicated but I could be wrong.

Thoughts?

 

[Krachek]

I think you went on the over complicated side of the Force!

 

[TaranTheWanderer]

I think you went on the over complicated side of the Force!

Yeah maybe, except every time I've ever done a Chase, people are raising their hands, "but what about this ability that I have?" I'm trying to incorporate most of those desires.

 

[Krachek]

Yeah maybe, except every time I've ever done a Chase, people are raising their hands, "but what about this ability that I have?" I'm trying to incorporate most of those desires.

Then you will have to make a set of rule for
Escaping the sewers
climbing the Cliff
finding Mr Z in the lower city of Shan
landing safely the airship before it explodes
if you fun and time ahead it is perfectly fine.

 

[TaranTheWanderer]

Then you will have to make a set of rule for
Escaping the sewers
climbing the Cliff
finding Mr Z in the lower city of Shan
landing safely the airship before it explodes
if you fun and time ahead it is perfectly fine.

Yeah, thanks for your advice.

 

[Swarmkeeper]

Not sure if I really understand what you’re trying to accomplish with setting the DCs. For example, it might be much easier to escape (or maybe easier to be caught depending who is chasing you) in a crowded city than in an open field or hilly terrain so... not sure DCs are even the way to go. Opposed rolls may be more appropriate with bonuses given based on each side’s familiarity with the terrain/environment.

In any case, chases can be a nice change of pace for a campaign session. Have fun with it!

 

[robus]

For chases i wouldn’t worry about DCs but complications. What are the obstacles both quarry and pursuers will have to navigate while engaged in the chase. Think about a roof top chase. The gaps between buildings will vary and the landing surfaces treacherous. Perhaps there are routes the PCs can use to gain on the quarry, perhaps there are things the quarry can do to delay the PCs.

Have these pivot points planned and describe them to the players their choices in the moment will determine what DCs to set (and 10, 15, 20 work well for most things). So rather than worry about mechanical systems think more about the chase itself and what’s going to make it particularly exciting and challenging.

 

[NotAYakk]

Can I propose a simpler chase structure?

Place everyone on a chase track, representing how far apart they are. A typical chase track is in units of 10'.

Everyone has endurance equal to their constitution score.

When you expend endurace and you run out, you gain a level of exhaustion and the only action you can do is recover. You can choose to expend endurance even if your endurance is 0 and just auto-gain a level of exhaustion, but this is usually unwise.

You get 1 action, and 1 athletics check per round.

Your actions fall into roughly these 3 categories:
a) Confound. Attempt to make raw speed unimportant.
b) Accelerate. Attempt to boost your own speed.
c) Decellerate. Attempt to slow down your enemy.
d) Escape/Capture. Attempt to win.
e) Recover.

(a) A successful confound means everyone's speed is zeroed this round. A failed confound means only your speed is zeroed this round. Costs 1d6 endurance.

(b) A successful accelerate gives you advantage on your athletics check. A failed accelerate means you have disadvantage on your athletics check. Costs 1d8 endurance.

(c) A successful decelerate gives your foe a 1d6 penalty on their athletics check. A failed decellerate gives you a 1d6 penalty on your athletics check. Costs 1d10 endurance. (if multiple decelerates are active, roll that many d4s and take the largest)

(d) A successful escape/capture ends the chase. Failure gives you both disadvantage on athletics and zeros your speed bonus. Costs 1d12 endurance.

If you don't like the endurance cost of an action, you can abort it and fail instead of paying the endurance cost.

(e) A recovery lets you expend a HD to recover (roll+con bonus) endurance.

After the action, everyone rolls athletics and adds half their speed unless someone confounded. (edit: halved speed bonus)

Subtract the fleeing person's check from everyone else. Move everyone else 1 spot on the chase track if they win, plus 1 for every 5 full points you beat or lose against them by. Natural 1s and 20s move an additional spot.

Accelerate options include using acrobatics to take a shortcut, casting jump, etc.

Confound options includes ducking into a crowd and attempting to lose your pursers.

Escape/capture attempts are only possible if the distance is great/small enough for the escape/capture attempt.