Monster A.I. for Old School D&D

[Druzzrug]

Hi, everyone. I'm new here. I've been having such a fantastic time since I learned about this site - and playing RPGs solo in general. I'm usually the DM when I get together with my group, which I don't mind at all, but sometimes it's nice to be the player. Playing solo is my only opportunity to do so. I've only been playing this way for about two weeks or so, but I've devoured a wealth of material in such a short amount of time: Mythic GME, CRGE, John Yorio's blog posts, and a host of other blogs and DriveThru RPG downloadable PDFS. My head is just spinning with ideas, and I've played a few satisfying "sandbox" sessions in a world I am creating as I go using Labyrinth Lord (Basic D&D retro clone.)

The point of this post, however, is that while there are plenty of mechanics for story twists and the like, I haven't found much in the way of enemy A.I. and general encounter setup. I have been toying around with a few ideas, though. I already know about random encounter tables and the like. Which enemies are encountered is not the problem; my concern is where are the enemies? Are they at range? Did they ambush us from behind? Do they not notice us? I know there are rules for surprise in old school D&D, but for the most part figuring out the the encounter layout has been a little challenging. I have been experimenting with rolling dice for distance and direction, but I'm not completely satisfied with what I"ve come up with so far.

I did come up with a nice little "Dirty Tricks" table to keep me on my toes. Here's how I'm using it for anyone who might be interested. Any input and/or other ideas are welcome and encouraged. Thanks!

During an opposition encounter, roll 2d6 initiative each round (per normal Basic D&D rules). On a tie, however, roll the opposition’s die once more. If it is not the same result, the PCs act first this round. If it is the same result, the opposition acts first this round. In addition to performing a normal attack, the first enemy to act (determined randomly) will perform a “Dirty Trick” against the closest PC. That PC is the target of the Dirty Trick. Roll on the Dirty Trick table below:



Dirty Trick Table

1. “Throw Dirt”. Save vs. Breath. Failure = target rolls attacks at disadvantage this round.
   
2. “Taunt” Roll WIS or under. Failure = target may not attack this enemy this round.
   
3. “Sweep the Leg” Roll DEX or under. Failure = target falls prone and the enemy attacks with advantage.
   
4. “Skullbash” Roll CON or under. Failure = target may not perform any actions this round.
   
5. “Critical” If this attack hits, it deals double damage to the target.
   
6. “Relentless” Roll on this table twice, disregarding results of ‘6’. (The same Dirty Trick may be applied twice, but any effects of a failed save or ability roll do not stack.)
   

[Sam]

I've wondered myself if there's a simple, mechanical way to take NPC actions entirely out of my hands, so even I'm surprised.  Seems like you're onto something.

[Jingo]

I personally think the MAG is a great tool to asking abstract questions for what the AI is doing or planning. Maybe try this. Roll the MAG button. Then jot down the first five things that logically come to mind given the scenario in your head. Then maybe roll on one of those to see which it is. Just a thought.

[Sam]

I can't use the glyphs for anything, either because I've never seen them used and therefore have no frame of reference, or because I lack the interpretive capacity to turn, say, a picture of bombs into something story-coherent. However, clicking "Action" under the Mythic tools could work.

[Druzzrug]

Interesting idea about the glyphs. I definitely use them, but I would like something less open to interpretation when it comes to encounter setup. I usually play with minis so that I can set them up on the table to be able to make somewhat tactical decisions.  

What I"ve been doing to set up an encounter is use two dice from an old TSR game back in the 90s called Dragon Dice. Instead of pips they have symbols. I use one die as an "Enemy Arrangement" die, and another as an "Enemy Strategy" die. I then use 1d4 to determine distance. For measuring distance, I use a pen (see "Enemy Distance" table to see what I mean.) Basically:

Enemy Arrangement (6 sided)

- (2 sides with dashed lines) enemies are directly in front of the PC
- (2 sides with circles) enemies surround the PC
- (1 side with a circle and skull inside) enemies surround PC and will act first.
- (1 blank side) enemies are not aware of PC (PC may attack first or flee)

Enemy Strategy (6 sided)

- (3 sides with swords) enemies will melee attack
- (1 side with an arrow) enemies will used ranged weapons (and will revert to melee if/when at point blank)
- (1 side with a skull) elite enemies - raise hd, damage, saves, etc., by 1. And melee attack point blank (no distance roll)
- (1 side with a face) enemies are willing to parley (roll Fate Dice or roll CHA check, etc.) Failure = enemy attacks.

Enemy Distance (4 sided)
- 1: Point Blank (minis touching)
- 2: Near (one pen away)
- 3: Far (two pens away)
- 4: Very Far (three pens away)

*Note on distance. PCs can make two actions per round. They can move and perform one action - attack, open a door, drink a potion, etc. Or they can perform two move actions. A move action is roughly the distance of a pen. So a PC could move to reach and melee attack a Near enemy in one round, or move to a Far enemy in one round and melee attack them the next. A Very Far enemy would take three move actions to be able to melee attack.

Of course PCs can attack at ranged. I usually do +1 to-hit bonus if enemy is Near, no bonus if enemy is Far, and -1 if enemy is Very Far. No ranged attacks are allowed at Point Blank. The same rules apply for enemies attacking the PC. My table isn't the biggest, so I generally stick to these four distances.


After the encounter setup has been rolled (enemy arrangement, strategy, and distance), roll initiative each round to see which side goes first. (See my initial post on this thread). Also, each round roll 1d4 for the enemy tactic.

Enemy Tactic (4 sided)
-1: Fight Defensively (+2 AC. Does not attack)
- 2-4: Fight Normally


This might look like a lot of rolling, but you only roll the encounter setup once - at the beginning of the encounter. Then you just roll initiative and 1d4 each round to see what the enemies will do.

This is what I've been using thus far.

[SparroHawc]

One thing to keep in mind is the intelligence of the enemies you're facing. if their INT is low, then they aren't likely to do much besides wail on you with whatever natural weapons they have at their disposal. If it's in the midrange, maybe they'll try to slink around you, flank, ambush, etc., but tactics during the heat of battle will be simplistic - swing at whatever recently hit them hard, that sort of thing.

If their INT is in PC range on the other hand, that's when the dice and prompts can really do work - especially if you're willing to consider their results to be retroactive. Setting up traps, having someone else hiding in the wings with a debuff spell / poison, arranging to bull-rush you through attacks of opportunity, that sort of thing. Or making mistakes / getting frightened if the prompts call for it. Then you can still be surprised by their actions even if there's no proper AI behind them.