Hacking 2e: Roll-Under Mechanics – Part 2

Last time, I looked at converting Saving Throws, Surprise, and Attack Rolls to a roll-under system. Let’s do the rest. Please note: this is mostly the “make a new ruleset for initiative" post and will constitute most of the text.

 

4. Damage

Unless we’re altering the hit point system (which I’m not looking to do today), this mechanic needs to give us a value to subtract from those hit points. With that requirement, converting damage into a roll-under check is a weird and torturous exercise. I think it could be done by giving every weapon two static damage values, then giving the higher damage value on successful rolls. However, this is sweaty and lame, and it provides zero advantage over a flat roll.

Rolling the value directly on the die is the cleanest way, as is adding modifiers to the die roll. Since this doesn’t align the goal of making everything a low roll and only adding modifiers to scores, I’ll need to add in a caveat for this type of roll.

Whenever you roll dice to obtain a result, rather than beat a score, you’ll want to roll high and add any modifiers to the roll itself.

Damage won’t be alone in this; Hit Dice and calculating starting gold also meet this criteria. 

 

5. Reaction

Again, I’ve got no static number to work from. Reaction roll results slot into a table, which provides a spectrum from ‘hates you’ to ‘best friends’. Since it’s not a pass or fail situation, I don’t see a way of altering it with anything other than a sledgehammer, which I don’t wish to do. It, like damage, thankfully matches the ‘if rolling high, add to roll’ convention, assuming that I put beneficial reactions in the high range. Also, players aren’t the ones who roll here; the DM is in charge of determining reactions. I think I can live with this one.

I could alter this system drastically. Players of later editions are used to rolling a Charisma check in the form of a skill (Diplomacy and later Persuasion), and we could pick this up and just drop it here, making a failure into a negative reaction and a success into a positive one. However, I don’t think I want to take this path. I like the idea of the granularity of reactions provided in AD&D. More importantly, I like that it’s not the players making an active roll, but is instead a tool for the DM to respond to character actions. We’ll come back to Reactions later, but this stands for now.

[Edit: I came back to it later: Here's my idea for converting Reactions to roll-under.] 

 

6. Initiative

This is the real pickle. 2e changed initiative rolls to a d10, with lower rolls beating higher ones. This appears to have been done to accommodate weapon speeds, since that system previously worked with 1e’s segments, and I’m just not going to talk about segments. It makes my head hurt, I’m not smart enough for it, and to be honest, I’m probably wrong.

Regardless, we’ve got a die roll on which we’re trying to roll low, but to which we’re adding modifiers directly. It’s messing up our whole setup. This could be solved by just flipping it to a ‘highest roll goes first’ mechanic, but damn it we’re trying to roll low and this is already doing that. So what to do?

Let’s head over to the OSR to see what they’re up to.

For the most part it’s a lot of rolling high on a d6, either individually or as side-initiative, sometimes with modifiers. This includes Old-School Essentials and Dolmenwood, Whitehack, Swords & Wizardry, and Hyperborea3e. Knave treads its own path with an interesting opposed Charisma check. Whichever way it’s done, it’s the players and the DM rolling opposing dice and comparing them to see who goes first. Therefore, it’s the same essential mechanic as what we’re trying to get away from.

Into the Odd and its derivatives simply have players go before the opponents. Surprise is a Dex save and failing it causes you to go after the opponents. Like every rule that Chris McDowall pokes at, this is elegant and easy to understand. However, it’s just too rules-lite for something that hopes to emulate AD&D initiative. Though the idea of Surprise affecting initiative order rather than creating an entirely separate surprise round is interesting and worth coming back to when we dive back into Surprise mechanics. Another day!

The Black Hack, Mothership, Cairn and Mausritter get a little closer to what I’m looking for. Here, you’re rolling against your own stat, with success putting you before the monsters and failure placing you after. I like this quite a bit, as it gives us a roll-under option and would subsume initiative into the Dexterity ability entirely (rather than having Dex give a bonus to initiative), but it would also over-emphasize that ability beyond what I’m comfortable with. I’ve already beefed that stat up like my fathers before me, and I don’t need it to be any more important than it already is.  

The winner today is the art kid wearing the Slayer t-shirt: MÖRK BORG. 

Its first listed option for initiative is another d6 roll, but not an opposed one. On a 1-3, enemies go first; on a 4-6, PCs go first. If you squint, you can see the check implicit in this 50/50 chance. The math suggests that all monsters have a static initiative score in the middle of the die range, which we’re rolling against. Let’s flip the roll to PCs going first on low rolls, up the die to a d10, and remove the listed ranges in favor of a single target value of 5.

All PCs have a base Initiative Score of 5, modified by Dexterity or circumstances. Success on this roll means the PC goes before the monsters, failure places them after. The order that players can take on either side of the monster’s turn can be based on the value of the die roll, with lower results going first, or this could be left to the discretion of the players, as in side-initiative.

Does this system justify itself versus a straight-up Dexterity Check? If we compare a flat Dex check to this new system using the previously devised Dexterity modifiers, we get this:

Pretty good. It's about even on the worst Dexterity scores, but keeps Dex from completely dominating initiative at the mid and higher ranges. This leaves room for some additional modifiers, and gives the monsters a chance.

As in the original rules, lengthy spell casting times still go at the end of the round, but the order that dueling wizards fire off their spells is determined by the PC wizard succeeding or failing the Initiative check. The same can be extended to additional weapon attacks.

As an additional option, weapon and spell speeds could be added to the mix by giving faster weapons or spells a positive modifier to the Initiative Score, while providing a penalty to slower ones. This would also be a more intuitive solution to weapon speed variables, as currently those speed values are higher for slower weapons, when they really should have a big minus sign in front of the number.

Particularly fast monsters could provide a blanket negative modifier to the PC's scores, making sure that some enemies are just going to go first unless you’re the speed demon in the group.

This is a heavy simplification, but it’s clean and doesn’t break anything (yet). What’s important to me is that it doesn’t fundamentally alter combat initiative in practical terms: PCs still roll, they still go before or after the monsters, and assuming we retain the features of the combat round (declaring actions before rolling and rolling each round), it meets the needs of feeling like the original initiative system.

 

Final Assessment:

Let’s look at the table again after the changes.

Modifier for…	Attempting to…	High or Low	Modifying
Saving Throw	Beat a Static Value	Low	Saving Throw Score
Surprise	Beat a Static Value	Low	Surprise Score
Attack Roll	Beat a Static Value	Low	Opponent AC
Initiative	Beat a Static Value	Low	Initiative Score
Nonweapon Prof.	Beat a Static Value	Low	Ability Score
Thieving Skill	Beat a Static Value	Low	Thieving Skill Score
Morale	Beat a Static Value	Low	Morale Rating
Damage	Get a High Number	High	Roll
Reaction	Place on a Spectrum	High	Roll

 

I’d say that’s progress. I’ve converted the majority of the systems to a roll-under mechanic, with only two exceptions. These two have their own consistent logic. Damage rolls are an attempt to obtain a numerical result; it’s a value for its own sake. Reaction rolls are used to compare to a value on a lookup table. Therefore, it can be stated that any die roll attempting to obtain a numerical value (rather than beat a static score) will have its modifiers applied to the roll.

Saving Throws and Surprise rolls are flipped on their head, but operate mathematically and procedurally similar to their original design.

Attack Rolls are mathematically similar, but with an entirely new procedure. It’s an oddball, since it has you add to a static value that isn’t on your sheet and is ostensibly unknown to you, but isn’t far removed from the original manner for determining To-Hit numbers and doesn’t add any new overhead.

Initiative is a major change, both in procedure and mathematical results. It loses the original system’s granularity and specificity, and eliminates the possibility of monsters and PCs acting simultaneously. In trade, it adds simplicity, clarity, and speed.

 

Well, that was fun. I think I need to dig into some of these systems a bit more before I consider them fully baked, but getting them aligned to the roll-under mechanic is a solid start. Since I’m on a roll with Initiative, let’s finish that out next time.