Last session I left the players on a cliffhanger encountering a minion of the BBEG called a "Conduit" that even the higher level npc traveling with them panicked and told them to run so they know that they should.
The "Conduit" can Telepathically communicate over a large range with anyone they are aware of so he will be taunting the PC's. He isn't interested in personally capturing them as he doesn't know them but they stumbled on his ritual indoctrinating new members to his group.
The scene is already mid evening and as the chase progresses the Conduits presence will make it seem to the players that it is slowly getting darker and darke even to the point of total darkness.
The Conduit is only persuing at a slow walk Michael Myers style. However he has about 16 or so followers with him. 4-5 are Brawlers (using the or Warriors Stat block with 1d6 brawling claws piercing agile) and 12-13 indoctrinated commoners so -1's wielding daggers or fist.
The Stages of the Chase I imagine will be
Run!(start and gain some distance)
Hide(try and hide amongst the forest to double back or change direction on the pursuers)
Total Darkness(designed to possibly split and scare the party this is where the conduit will taunt the players mentally)
See the light(after being pursued for what very well may be hours the pcs see a light in the dark and end up at the gates of the settlement they were going to greeted by confused guards who saw them running around like chickens in the night with no one chasing them.)
Edit party level 3rd
Sounds like fun.
First question to ask: what happens if the players don't succeed?
For more mundane things and putting details on your ideas so far: Looks like using a standard VP Chase setup should work just fine. I would have Run and Hide be two tactics that the players can use during the chase sections. Total Darkness and such could be potential penalties for failing at chase progress. The See the Light would be the end stage of the chase where the players successfully escape.
So a typical chase like this would be set up with some number of sections, and some time interval where skill checks are done. Each section takes a certain number of points to progress past. The enemies progress a fixed number of sections in a fixed amount of time. Usually one section per time interval. Then the players try to accumulate enough points to progress past the sections faster than the enemies do.
Standard DC for a 3rd level challenge is 18. Adjust that according to how appropriate the skill is and whether you want the players to succeed more often or less often. As was noted in a different thread, usually in a chase you need to either have a lower DC so that the players crit succeed more often than they fail, or require fewer successes to progress past a section than the number of players participating.
If you don't have a good answer to that first question, I think it might be better to pretend to set it up like a chase, but actually have the rolls mean nothing and the points don't matter. Just have the players roll as though they are trying to escape, keep track of how many skill checks that they fail and adjust your description of things accordingly, and when the players are sufficiently tense, let them escape.
If they completely fail I will have them black out and be found by the rangers of the nearby settlement and have had the bad guy probe their mind matbe leave some "Would you kindly" trigger in their Psyche for a later date. Ultimately I want the players to learn about this bad guys existence and power while giving them fun interations without me just saying hey this guy is scary. You run away ok next day.
OK. Then I would set up the math as such:
5 sections. Time interval of 1 minute.
section 1: run. DC 16. skills: athletics, acrobatics, or fortitude (not really a skill, but you can calculate a fortitude bonus and use that the same way - love the uniform scale of everything).
section 2, 3, 5: run DC 16 or hide DC 18. skills: athletics, acrobatics, fortitude for run; stealth, survival, deception, or appropriate lore for hide.
Throw something strange in for section 4. Maybe make it have an occultism barrier DC 14. Option of society or will at DC 18. Some mental attack from the enemy chasing them.
You didn't mention how many players there are in the group, so I will simply call it 'n'.
Each section will need n successes in order to pass. Once the players pass one section, they immediately move on to start on the next. The one minute time interval passes after all n characters attempt one of the available checks. Players can choose their order, but they can't skip their turn. Players get one round free. Every minute interval after that, the enemies gain one section on the players. Standard stuff for the Chase system.
If the players make it through all 5 sections, they get to safety. If not, then apply your failure result.