80
You can really tell that they wrote parts of the module before publishing the rules…
(ttrpg.network)
For reference: There is a duell in the module where a shaman tries to secretly help one NPC by continously casting Cure Wounds on him while supposedly only helping him "stand up" after he intentionally let‘s himself fall prone. To spot this, a PC has to specifically declare checking for interventions a then suceed a DC 15 perception-check despite being within earshot…
Yes they could. But they did not. That's what I'm crititicising. Perception is one of the most used skills ever. It would not have hurt not to use it here. And if you really want to, then give her some kind of ability that actually let's her do that, because these kind of things can be missleading to new players/DMs and puts extra work on the DM.
And I really like less strict systems like M&M too, but if you write something in a more rigid system, you should adhere to the rules of that system. Or in this case: You shouldn't start writing full on adventures in an unfinished system.
But that's my point, 5e is already not a rigid system.