Manbearcat
Legend
This is full of jargon I do not understand.
When running traditional games like D&D or Savage Worlds, I don't like hinging everything on a single roll. So, if the ranger flubbed his stealth check it would produce a response from the wyvern, which would lead to a new situation the PCs attempt to deal with, and on until the situation is resolved.
That said, I tend to use journey rules for travel, so the wyvern encounter is already happening as a result of some other (complex) check.
What things do you not understand? I'll gladly clarify. In the post I already defined Disposition, Factor, stakes, Defend & Attack (in a Flee Conflict). Scout and Pathfinder and Twist and Condition should be obvious what they do.
Order of Might just means "physically more capable than you" (its a relative number) so bad stuff mechanically in physical conflicts/tests.
I described exactly how Torchbearer handles this exact situation; how the gamestate evolves:
Wyvern Brood but no Wyvern > Sneak around Brood to Glacial Pass > Crap Wyvern! > Crap FLEE! > Conflict to see how Fleeing resolves > Win Condition reached (they flee to safety) > Minor concession required due to Order of Might difference > Pathfinder Tools lost (down a crevasse).
I know the 5e Chase Rules. Have you used these? Have you used these in a similar situation (PCs fleeing a threat they couldn't surmount or didn't want to attempt to surmount)? Can you give us an excerpt with some mechanical underpinnings?