In my last D&D session, the party I DM for was being chased by unknown pursuers in the wilderness, while unrelated clans are at war with each other in the vicinty. This was made quite clear in earlier sessions. I created this mechanic to try to simulate the chaos of trying to cross an active battlefield while losing their pursuers. I made a giant map for it (120x90) for our VTT. There are two phases: Movement and Engulfed in Battle. My party is 7 PCs at level 6, so the DCs, etc are tailored to them. I thought I would share my creation as my players found it quite fun once they got the hang of it.

Intro: The party is still being pursued by an unknown entity, now only a few minutes behind them. Localized battles are raging on all sides. Each round, the battles will shift direction and distance randomly (1d8 for direction and 1d4 × 5 ft).

Round Sequence

1. The party chooses a movement option.
2. Resolve movement phase.
3. Battlefields shift as per random rolls.
4. If Engulfed, resolve Engulfed combat.
5. Apply Pursuit changes.
6. Repeat.

Moving Across the Map

The party moves as a single, unified group. The party only has 60 ft of vision to simulate the dense forested terrain they are moving through. Each round, the group must collectively choose one of the following movement options:

1. Stealth (Leading Horses by Hand)

• Movement: 15 feet.
• The Benefit: No Animal Handling checks are required, and you are not immediately seen.
• The Risk: You move incredibly slowly. (+2 Pursuit). You can still be engulfed by a randomly shifting battlefield, however, all rolls are made one degree better (a roll with disadvantage becomes a regular roll and a regular roll becomes a roll with advantage).

2. Mounted Travel (Normal Pace)

• Movement: 60 feet.
• Checks: The horses smell blood and are terrified. Each rider must pass a DC 10 Animal Handling check. The rider leading the pack horse must make a second check for the pack horse at Disadvantage (for a total of 8 checks).
• Failure: Each failed check reduces the group's total movement speed for the round by 10 feet (to a minimum of 10 feet), as players have to split their attention to wrangle the skittish mounts. For example: If 2 players fail, the group moves 40 feet. If 5 or more checks fail, the group is reduced to a crawl of 10 feet.
• Individual Penalty: Any individual player who fails their own check by 10 or more (rolling a 2 or lower) is thrown from the saddle and takes 1d8 fall damage. No other penalty is applied to the individual.
• Pursuit: +1 Pursuit.

3. Spurring to a Gallop (The Blitz)

• Movement: 120 feet base. Due to how noisy this is, all nearby battles automatically shift 15 feet toward you.
• Checks: DC 13 Animal Handling check for all riders (7 PCs + 1 Pack Horse).
• Failure: Each failed check reduces the group's total movement speed by 15 feet, as players must split their attention to manage their extremely skittish mounts. For example: If 2 players fail, the group moves 90 feet (120 ft - 15 ft - 15 ft). If all 8 checks fail, the party is completely halted and doesn't move at all that round.
• Individual Penalty: Any individual player who fails their check by 5 or more (rolling a 10 or lower) is thrown from their saddle for 2d8 fall damage. No other individual penalty is applied.
• Pursuit: The Pursuit modifier is dependent upon your movement:
  • If final movement is 91+ feet (0–1 failures): You leave them in the dust. (-1 to the Pursuit tracker).
  • If final movement is 60–90 feet (2–4 failures): You hold your lead. (0 to the Pursuit tracker).
  • If final movement is 0–59 feet (5+ failures): The chaos halts you, and they close in. (+1 to the Pursuit tracker).

Other Movement Options

• Scouting Ahead: Instead of moving during a round, you can pause to scout. While you wait, the pursuers close the distance:
  • Owl Familiar: Grants a general layout of heavy fighting zones. (+1 Pursuit) for each round of scouting.
  • Stealth Scout: Safely triggers/tests a zone alone without risking the horses. (+2 Pursuit) for each round of scouting.

Being Engulfed in Battle

Each battle has an Awareness Zone. If you are caught inside of one—either by walking into it or having the battle shift onto you—you must stop moving and fight your way out.  This challenge uses abstract, macro-combat rounds. You cannot use Extra Attack, Action Surge, Flurry of Blows, or other class/subclass combat features. Spells are limited to attack cantrips.  Damage dealt is irrelevant; only whether the attack hits matters.  The party can become Engulfed if they wish to try to cut through a battle.

Awareness Zone: 70 ft radius.

Checks: At the start of your turn while engulfed, you must make a DC 13 Str or Dex Saving Throw or take 1d12 damage on a fail from the random arrows, deflected blades, and chaotic melee swirling around you.  Evasion/Barbarian Rage/etc. still halves damage.

Player Actions: Your horses are not trained for battle, and staying mounted while Engulfed is not an option.

You have three options on your turn while engulfed:

• Dodge and Control Horse: Focus entirely on survival. You make your initial Str/Dex Saving Throw with Advantage, but make no attack, contributing +0 to the Break Free bonus.
• Hold Reins and Attack: You hold your horse’s reins with one hand and strike with the other. Make a single simple attack or spell attack cantrip against AC 13 at Disadvantage.
  • Success: +1 Break Free bonus.
  • Fail: +0 Break Free bonus.
• Hand Off Reins to a Dedicated Holder: You drop your reins or hand them off. Make a single simple attack or attack cantrip against AC 13 normally.
  • Success: +2 Break Free bonus.
  • Fail: +0 Break Free bonus.

Other Engulfed Rules

• Natural 20: Double your contribution (+4 Break Free bonus).
• Natural 1: -1 penalty to the Break Free roll.
• The "Dedicated Holder" Limit: A person can only hold one other set of reins (such as the pack horse or an ally's horse). If you are holding an extra set of reins, you cannot make an attack.
• Allowed Special Abilities: Any abilities that modify rolls or provide situational advantages may be used (for example: Bless, Luck, or similar features). These abilities consume their normal action/resources.

Breaking Free: To escape the melee, the group must make a single collective d20 + Break Free bonus roll at the end of the round. You need to exceed a DC 13 to escape. If successful, you can use 60 feet of movement to choose where you exit the Awareness Zone. If they fail, they stay engulfed and repeat the process next round.

Cutting Straight Through: It is possible to decide to cut straight through a massive battle. Doing so requires a minimum of three rounds, as you need three successful Break Free rolls to make it out the other side. 

• Pursuit: +1 Pursuit penalty is still applied for each round you are stuck inside.
• The Reward: If you successfully complete the three rounds and make it through, you receive a massive -6 to Pursuit, as the pursuers are now completely blocked and delayed by the raging battle lines you just navigated.

 Order of Operations (When Engulfed)

1. Players declare which stance/option they are taking.
2. Players make the required Strength/Dexterity Saving throws (DC 13 or take 1d12 damage).
3. Each player carries out their action (such as their single AC 13 attack roll) and notes their contribution to the collective pool.
4. One designated player rolls a flat d20 + the accumulated Break Free bonus to determine whether the group Breaks Free.

Pursuit

• If Pursuit reaches 10: The Pursuers have caught you. What happens then will be determined in the moment.
• If you cross the northern edge of the map: If you make it to the other side before the tracker hits 10, you have successfully lost them.

Pursuit	Description
0-2	Sounds distant
3-5	Shapes visible behind you
6-8	Pursuers are close enough to be identified
9	The Pursuers can be clearly identified