Experimental rules for co-op games

[Antarius]

This is my foray into creating an "AI" for playing smaller "RP-type" or squadbased missions without the need for a dedicated gamemaster. My group and I played a short campaign (five or six games) and ironed out a few problems, but it is still very much a work in progress.

 

So far, what we have done is, I've created scenarios and stories, but constructed them so my knowledge of what was going on wouldn't impact the game (for example, in one scenario we had to find an exit from a crashed space hulk, so I marked 3 different possible exits and randomised which was the right one, so I didn't know more than anyone else).

 

Other things that could definitely be done would be creating tables (or similar) for random battlefields, enemies etc. - essentially creating a "random scenario generator" so you don't have to have to write a story, plan scenarios and so on, but so far all I've done is create the basic framework.

 

A final note is that the "Enemy Behaviour" tables assume enemies that are reasonably manageable by the player characters. Assuming you want to make a "boss battle" or similar, it is probably best to ignore the "reinforcements!" result.

 

Without further ado, here are the rules as they are at this time:
 

Co-op Rules

 

The general concept of these rules is to allow players to play a co-operative squad-oriented/”light roleplay” type game, set in the 40K setting. The following rules assume that players control 1-2 models each, although you could add more, if you wish (and you don’t mind the extra bookkeeping).
 

The basic rules are either the 40K rules OR the Necromunda rules (they are close enough that either should work and that profiles from one game can be “lifted” into the other, if for example, you use the Necromunda rules but need stats for a Carnifex or similar).

What I have playtested so far has been the basic Necromunda rules, with the following exceptions and additions, but I see no reason why you couldn’t use the basic 40K rules instead.
 

Important differences from the regular Necromunda rules:

• No alternating activation; instead there’s a Player turn and an Enemy turn.
• You can choose targets freely
• Instead of the regular charge rules, charge is a basic action that gives you 1d6” move to get within 1” of an enemy model-
• There is no ”Pinning” (unless you want there to be)
• When ”player characters” lose their last wounds, don’t roll the injury dice – instead they are considered to be “down” (i.e. players don’t go directly OOA, not even in melee).
• When ”down”, players roll 2 injury dice in the recovery phase and pick their preferred result. This increases to 3 dice, if there’s a fellow player character within 2”
• Enemies don’t roll injury dice – they go OOA when they lose their last wound (unless you prefer otherwise and don’t mind the extra bookkeeping)

 

The ”AI-system” aka ”Enemy Behaviour”

In order to make the system work without a dedicated “Game Master”, I’ve come up with the following “AI” that controls the enemy groups by rolling dice and consulting a table. The idea is that you should be able to figure out what an enemy will do without expending to much time and energy, but also having some unpredictability, so players can’t “game the system” too much.

 

Feel free to add variations, depending on the scenario, etc.

General rules for enemy behaviour:

• Enemies always seek targets (PC and any non-enemy aligned NPCs). Enemies are said to have acquired a target if there’s a valid target within line of sight + range of one of their attacks.
• If enemies have several potential targets they will pick the closest, unless there’s another valid target that would be easier to hit (i.e. they might fire on a target that is farther off, but not in cover).
• Enemies keep 1” away from other enemies (unless they are ”grouped up” – more on this later)
• If an enemy model moves within 1” of a target they count as charging.
• If Enemies do not have any shooting attacks, they will always attempt to move into melee.
• If Enemies are ”reactivated” for any reason (usually due to rolls on tables) they will still have a limit of moving x 2 and shooting x 2 in a turn (unless something else is specifically stated, such as ”move x 3” or similar)
• Enemies “group up” if they move within 1” of each other (usually due to the “group up” action) after which they will move and fight as a group, rather than rolling individually for each model.

 

All Enemies have a Type, determined by whether it has any Ranged Attacks, or it only has Melee Attacks.

All Enemies also have a Temperament: for example Ferocious or Cautious, which determines how they will act in specific situations (this is described in the relevant behaviour table)

 

Eemies with Ranged weapons:

 

1. ”Temperament Action”
   Ferocious: 1 x move, does not care about cover, shoot x 1 (2 x move, if impossible to acquire any targets)
   Cautious: 1 x move, prefers cover over proximity to targets (but does still seek to acquire targets, which may potentially cause them to move into melee), 1 x shoot (2 x move, if impossible to acquire any targets)
2. ”Group up”

If not already ”grouped up”, 1 x move if this can take them within 1” of another Enemy of the same type. Once grouped up the entire group takes a ”Temperament Action”.

 

If already in a group, the entire group takes a ”Temperament Action” instead of seeking to group up with additional Enemies.

1. ”Take cover”

1 x move towards cover (ferocious Enemies  prefers proximity to targets over getting into cover, cautious Enemies prefer getting into cover), 1 x shoot.
If impossible to acquire targets, take 2 x move towards cover.

If already in cover, 1 x shoot.

1. ”Aim and Fire!”.

Aim (+1 to hit) x 1, shoot x 1.
If there are no acquired targets, this result counts as a ”Temperament Action” result instead.

1. ”All Guns Blazing!”

2 x shoot.
If there are no acquired targets, count this result as a ”Temperament Action” instead.

1. ”Reinforcements!”

Add 1 model to the group, take 1 x move.

 

Enemies with (only) Melee attacks:

1. ”Temperament Action”
   If it is possible to get into melee with a target by making a 2 x move, do so.
   Otherwise
   If ferocious: 2 x move, do not consider cover.
   If cautious: 1 x move, 1 x hide (if the Enemy is within LoS and cover of a target. Otherwise take 2 moves), prefers moving into cover.
2. ”Group up”

As described in the table above.

1. ”Forward!”

2 x move (preferring cover to moving in a straight line but still seeking to get into melee)

1. “Obfuscation”

1 x move + counts as being in cover until next activation. (whether this is achieved by sneaking, throwing smoke grenades etc. does not matter for gameplay purposes)

1. “Furious Charge”

3 x move(!)

1. “Reinforcements!”

Add 1 model to the group, take 1 x move

 

Guard behaviour

 

In addition to the above, Enemies can also be considered  ”Guards”, in which case they are linked to an objective (depending on the scenario in question). Guards use the same tables as other enemies of their kind, but will always prefers proximity to the objective above proximity to targets, until the Enemies move within 3” of the objective they want to guard.

After getting to their objective, they will stay within 3” of it, unless their move would allow them to move into melee or let them acquire a shooting target (but they will move back within 3” as soon as possible, as they are still considered Guards).

 

Note: notice that the ”Guard” rule allow you to make enemies that “storm” a specific location, race the players to a certain objective or similar, rather than just patrolling and defending. If the rule seems slightly more convoluted than necessary, it is because I wanted to allow for one mechanic to serve all these purposes.

The whole thing is by no means extensively playtested, but so far it seems to work. If in doubt, try placing a couple of different Enemies of different Types and with different Temperaments on a battlefield and see how they act when you use the tables and/or the Guard designation, as it is probably easier to “get it” that way
 

Edited February 13, 2022 by Antarius

[Ace Debonair]

I really like this, it's a much more elegant (And simple) version of something I was working on for my own games.  
I had one table for each faction (for a total of six factions), disregarding armament, which meant each roll resulted in a LOT of instructions to account for any eventuality. 

 

This though, would work very easily for just about any enemy.

 

The best part about your system, to my mind, is that enemies could easily switch Temperament on a trigger when needed; for example when confronted by a hated foe or if something they are protecting is threatened, turning them from Cautious to Aggressive. Lots of narrative potential! 

 

 

[Antarius]

I really like this, it's a much more elegant (And simple) version of something I was working on for my own games.  

I had one table for each faction (for a total of six factions), disregarding armament, which meant each roll resulted in a LOT of instructions to account for any eventuality. 

 

This though, would work very easily for just about any enemy.

 

The best part about your system, to my mind, is that enemies could easily switch Temperament on a trigger when needed; for example when confronted by a hated foe or if something they are protecting is threatened, turning them from Cautious to Aggressive. Lots of narrative potential! 

Thank you! And yeah, I was really going for a mix of simplicity and narrative potential. The scenarios we played had some "trigger events" that would do different stuff, but I hadn't actually thought about Enemies changing temperament - that's a great idea :)