Zweihänder‘s a fantastic game, but one of the aspects I’m less enamoured of is skill assists. When one PC wants to help another complete a task and has a relevant skill, the the latter PC rolls an extra d10 and can replace either of the numbers of their d100 roll. It’s a very simple system which, however, from my perspective suffers from a couple of weaknesses (apart from seeming very powerful):
Firstly, there’s no extra rolling and therefore no suspence as to whether the assist actually worked or not, or whether, indeed, the ‘helper’ ended up getting in the way.
Secondly, and more importantly for me, only one person can assist. There is, in other words, no mechanic for teamwork on a collective task. (With crafting, teamwork only reduces the amount of time required.)
This bothered me when it looked like I was going to be running a maritime campaign with Zweihänder. One of my favourite teamwork mechanics is in the brilliant, but little-known Napoleonic naval game, Beat to Quarters (available as PWYW on Drivethru here; and I can also recommend its infantry big brother, Duty & Honour: here). In BtQ, naval combat is resolved by a single roll (or card draw in this case), just as it is in the Zweihänder naval supplement, Maelstrom. But BtQ allows everyone to participate in whatever way they narratively want: you decide what cool thing you’re doing that round, and every success adds a bonus to the final draw. And it could be anything: maybe you are using your craft skills to repair damage to the ship, or your charm to calm the lady passengers. You tell the story and, if you succeed, your side gets a bonus.
So I started to look at other d100 games to see how they did assist mechanics.
As for as I can tell, 1e doesn’t have assist mechanics and nor does 2e, although in this case we do have a +10% bonus To Hit per extra person ganging up on an attacker, so we could take that as a guideline. That’s the bonus given in 4e to assisted Skill tests, with the restriction that the helper has to have at least one rank in the skill being rolled and the number of helpers maxes out at the main character’s characteristic bonus.
Basic Roleplaying (a.k.a. The Big Gold Book)
All characters make a skill roll. The character eventually using the skill gets a 10% bonus for every successful assist roll (15 for “special” successes, 20 for criticals, -10 for fumbles). The maximum possible bonus cannot exceed the main character’s own skill level.
Renaissance Deluxe/Mongoose RuneQuest II/Legend
Every assisting character adds his “critical score” (i.e. 10% of his skill) to the primary character’s skill, and the primary character then rolls to see if the project was successful.
As above, but the character adds twice their critical score, with the caveat that it doesn’t effect the chances of a critical success.
Assistance from someone with the same skill makes task one level easier, i.e. +25%. In rare cases, it makes it two levels easier, i.e. +50%.
For Zweihänder, then, the Big Gold Book presents the best model for supplying suspense and teamwork. In this case, each helper would roll and a success would grant a +10% bonus, a Critical Success +20%, but a Critical Failure -10%. For assisting an individual, the number of helpers could be restricted to the main character’s relevant Characteristic Bonus, à la WFRP 4e, and any bonus would not affect the chances of a Critical Success, à la Mythras. For larger-scale teamwork, like in naval battles, those restrictions needn’t hold. In both cases, I wouldn’t restrict the choice of skill by the helper to that of the main one being used: if the player can justify using a different skill narratively, then that should be encouraged.