I just read that on r/osr and it made me think.
How to deactivate or avoid a trap without making a roll? Is it possible? Of course it is, let’s look at some examples:
Referee: To one side of the road there are bushes with wild berries. They look delicious.
Player A: I approach and start collecting blackberries.
Referee: A snake bites you. You are dead.
Player A: Oh, come on!
Player B: With a ten foot pole I examine the bushes for any dangers.
Referee: When lifting the pole, a snake has curled into it.
Player B: I throw the pole like a javelin and collect berries.
Referee: There’s some haze but you can see the bridge well.
Player A: I advance to the other side.
Referee: You fall and die.
Player A: What?
Player B: I advance slowly so as not to slip.
Referee: You get to the other side without problems.
Referee: In front of you there is a door.
Player A: I open it.
Referee: You activate a trap. You feel the needle, but you are dead before your body hits the ground.
Player A: Fuck you!
Player B: I look at the lock for traps.
Referee: You don’t see anything.
Player B: I use my lockpicks to try to disarm the trap, if there is one.
Referee: You trigger the trap. You are dead.
Player B: Why? It’s not fair!
Referee: Okay, you disarmed it.
Player A: It’s not fair! You killed me, and you let him live!?
There it is. Traps without throwing dice. Lovely, ennit?
In the first two cases, success is automatic if players take some precautions, but then failure is also automatic if they do not. Is it unfair? No. No, it’s not. It’s not unfair but it might seem so and people’s feelings might get hurt. Adjudication made sense in both cases, but from the players’ perspective, it can seem arbitrary.
In the third case it’s more difficult to adjudicate success or failure by just following the fiction, since suspecting that there is a trap and trying to deactivate it, is no guarantee that it will be deactivated. Both success and failure feel arbitrary, unfair, and even like cheating. A referee’s job should be easier.
That’s why baby jesus invented dice rolls
When players fail after making a dice roll, they won’t (usually) blame the referee or believe that their failure is an injustice, but a product of chance—although in reality it is not (only) chance: A failure isn’t the fault of a bad roll but of a bad decision. You can always choose not to cross the bridge, not to collect berries, not to open the door, doing something else instead, and return later, when you have made preparations, purchased potions, or whatever.
If we follow the rules of the game (as we are supposed to), Mr. Player A will have the opportunity to make a Save versus Poison to avoid dying from the snake bite, and a Save versus Paralysis to avoid falling into the abyss. And both players will have the opportunity to disarm the lock trap with a successful Tinkering roll (or equivalent), and to avoid damage if this roll is failed, making a Save versus Poison; they could even have a bonus to the first roll if they have tools (such as Player B).
Sometimes you really have to throw dice to discover or disarm a trap (like the proverbial poisonous needle in a door lock), and to avoid damage (or dying) if the first roll was failed.
Other times the trap is evident (such as the slippery bridge) and it only requires one roll to avoid its effect, and success can be automatic (at the referee’s discretion) if appropriate measures are taken (such as walking slowly, wearing mountaineering boots, &c).
Finally, at times the trap is discovered and deactivated by performing a specific action (such as the snake between the bushes with a pole), and would only require a roll to avoid the effect if activated.
A little advertising
Get a good book of traps! It’s a collection of a bunch books written by Steve Crompton and others, published by Flying Buffalo back in the 80s and 90s, reprinted here by Goodman Games. The first is also an affiliated link, so I might earn a few silver coins if many of you buy the PDF (which I will use to buy more RPG books).