How I'm building Jungle Zone 1 and the world around it in Unreal Engine 5.
One connected zone with four landmarks, each with its own missions and flow, linked by walkable paths with no fast travel and reached from two landing zones.
One solar system with three planets (Jungle, Snow and Desert), each split into three zones. Players deploy from the Galactic Space Station, land at a deploy point and work through missions on foot. There's no fast travel inside a zone, so the routes between landmarks are designed spaces, not loading gaps. Mission variants (kill conditions, timers, location shifts) and cross-landmark missions reuse the same spaces in new ways.
The Galactic Trade Port is a space station run by the Galactic Federation, a neutral body that's corrupt in practice. Factions rent embassy space on it, and whoever funds the Federation most gets the biggest embassy, the best placement and the shortest walk to the landing bay. None of that is explained; it's read from the floor plan. A black-market contact moves between a fixed pool of hidden spawn points on every visit and avoids the embassy zones, so players learn the outpost by searching it.
Zone 1 uses three colours so players can read who controls a space before they see an enemy: light blue for cyborg-run areas, light green where the parasites have taken over, and orange for the Nest.
Two landing zones give different first reads of the same space: Alpha on the west side by the docks, Bravo on the southern trail.
The cave runs Entrance → Forward Camp → Mine → Egg Chamber → Pre-Hive → The Nest. It's fully open and non-linear, with every area connected at all times, and two branch points create four route combinations. Because the hive always regrows in the lore, Hive Destruction missions can return without breaking the world.
Terrain, docks, outpost buildings and the cave entrance are blocked out in UE5 with Nanite and Lumen. The Forward Camp is in progress, with the Mine next.