>>95914561 (OP)
It really depends on what parts of fortnite you're wanting. The battle royale aspect or the walls closing in aspect? For the later maybe looks at how nightreign works. That seems a better parallel. Not because of the setting but because of how it works mechanically with RPG type mechanics.
Whatever you do, it will play like a dungeon crawl. You're moving from one point of interest to another with random or planned encounters inbetween.
For a shrinking map:
>have a rough map drawn just to show points of interest and where the players are
>either have it shrink after specific milestones or encounters, or add RNG and roll to reduce the size. Players take damage when outside it.
For battle royale aspect:
>make a list of encounters, have some of them at points of interest on the map and others as random
>make a list for random encounters and number them so you can roll for them, or write them on note cards you can draw.
>don't make them too mindless, have some social interaction with some encounters. Depends on your setting. Are there any reluctant participants in this? Are all the encounters with monsters? Is anyone trying to game the system and pretending they want to negotiate with the party?
>if the map is shrinking have it shrink after key encounters or specific numbers of them.
Have an end goal in mind. Do they fight until they're the only team left, or is there a boss waiting for them at the center of the storm? It may only be mechanically like fortnite. Maybe the whole planet is crumbling and you're racing to the last shuttle off world with only enough room for a few people. Whatever you're actually wanting.
