This lack of complexity is, of course, one of the appeals of Moldvay/Cook D&D. However, I know my players will, eventually, want to pull some fancy maneuvers, and it would be best if I’m ready for that sort of thing. Restraint here is important, since I don’t want to just recreate all the complexity of later versions of the game. I’ve already got copies of 2e; if I wanted to play that, I could start tomorrow and not waste a lot of time reinventing that wheel.
The temptation to build a standardized mechanic is strong, of course. That’s the solution modern game design theory crowns as the best. However, I’ve also already got True20 if I want to play a modern game. There are very real benefits to standardized mechanics. However, this exercise is not based on maximizing those. This game already embraces a legacy of lots of tiny different mechanics for different jobs. I see no reason to swerve from that path now.
People love spilling ink about grappling rules, and they tend to be the most complex monsters out there. A good set of grappling rules need to do two things: first, they need to model what grappling does, which is allow one or more combatants to immobilize and wrestle a foe to the ground. However, the ability to take an opponent out of the fight, regardless of how many hit points that foe has, is extremely powerful. If you make the grappling rules too powerful or flexible, fighters will just leave their swords at home and grapple everything they meet.
Here’s how I’m tackling grappling:
If you want to grapple someone, roll to-hit as normal, do damage as bare-handed. If you do more damage in that round than your foe, they are grappled and may not move or attack anyone else until they break free. Grappled foes do damage as bare-handed. They break free on the round they do more damage than you.
Because of the way my initiative rules work, a bare-handed grappler goes after almost any weapon-wielder. You have to get past that sharp-and-pointy before you can start to wrestle your foe to the ground. And if you don’t, you’re repelled. You can try again next round, but you didn’t manage to get a good grip on your foe this round. Once a foe is grappled, their movement is so limited they can only strike at someone who is grappling them, they don’t get the full benefit of their weapon, and they can’t move until they escape the grappler’s hold.
Also notice that multiple attacks seriously increase the chance of a successful grapple. The first grappler has to do more damage than the target. The second grappler, however, only has to hit the target; assuming the target can only hit one foe per round, the target will be doing zero damage to the second grappler. This means three or more grapplers are almost certain to get a good hold on a foe. That feels right to me, though it may put the PCs at a disadvantage. I can imagine swarms of kobolds wrestling the PCs to the ground. Or a few PCs wrestling a giant down. Ok, that seems like it might be a bit much, so here’s an addendum to our wrastlin’ rules:
If the combined heights of all grapplers is less than 3/4th's the height of the grappled, then the grappled can't move but can still fight with a weapon as normal. If the combined heights of the grapplers is less than 1/4th the height of the grappled, the grappled breaks free automatically.
So, lone gnomes will not be wrestling storm giants to the ground in my game. And one or two kobolds are probably not a serious threat to a human fighter. But enough of them can pull even a big man to the ground.
I don’t plan on using these rules very often against the PCs. I’m a little worried that they might be too useful in high-level combat, when the PCs and NPCs might have dozens of hit points. I might just have to play with the rules and see.