Restricting the npc spawn to only beaches is a bit annoying for builders, dont you think?



Maybe making certain "Team Furniture" be required within rooms in order for npcs to spawn and move in?



For example, the tribes would have to craft a relic with clay and place it inside the room.



There would be one relic for each team color. Rooms with a relic of one team cannot have the relic of another team placed and relics can only be removed by players of the same team color.



Additionally, Npcs spawning for a room with a relic cannot talk or interact with players of a different team.



Finally, npcs spawned within relic rooms do not appear on the map or npc moving screen for players of other teams.







This would allow tribes to create their base anywhere on the map and just need a single furniture piece to obtain tribe exclusive npcs.



A point to note is that you should ensure that npcs dont appear on rooms without the relics while the mod is activated to prevent 3 or more versions of the same npc spawning when theres only two tribes.

[doublepost=1465200495,1465200036][/doublepost]A second detail of this mod is proggression.



How would you prevent a tribe from entering the dungeon after the other tribe defeats skelletron?



How to avoid a tribe collecting hardmode items after the other one defeats wall of flesh?



How to prevent one tribe from collecting dungeon items after the other one defeats plantera?





I dont think its possible... so instead of limiting progress forcefully, how about giving the tribe that FIRST kills a boss a unique reward?





Invasions are even simpler. Keep a kill count of all monsters killed by each tribe and reward the tribe that killed most enemies with the unique reward. The kill count can be in a point value similar to the Moon events with tougher mobs giving more points.







This will ensure that the tribes actually compete for that first kill!

[doublepost=1465201068][/doublepost]In order to ensure the world is big enough for two tribes, messing around with world gen can be key.



Giving a single world two dungeons of different colors on either side of the map can serve as an early game stronghold against the rival tribe.



Two jungles in the map can be seen as much, but two temples may prove useful to allow players to prepare for war.



Separating the Desert and Snow biomes to both sides of the map can serve as a means for trade. As is the generation of Crimson and Corruption on opposite sides of the map.



Keeping the center of the map as Pure forest and Hallowed on hardmode can allow both tribes to benefit of the biome.





Allowing the generation of all ores both prehardmode and hardmode can prove key to ensure that trade (or theft) exists. Ensuring that certain set of hardmode ores spawn when a respective altar is destroyed can also be seen as a neat detail (demon altar = original ores, crimson altar = newer ores)







The main problem here is programming such a thing.