Edit: In the recent Q&A during the NA Fan Fest 2018, Yoshi-P stated that they have been experimenting with PvP servers where different GCs could engage in open world PvP. They said they had no plans for this now, however they told people who wanted this to be vocal about it. With the recent announcements of being able to jump worlds, one PvP world per DC would be something I want.
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I love open world PvP. I remember Yoshi-P having thoughts about PvP servers, if there is enough demand for it.
... but let's say that never happens. How am I going to get my open world PvP fix?
Well, give us an open world PvP zone. No instance, just a regular zone, but with PvP. I think it could be fun. A couple of ideas:
1. Have 2 (or maybe more) factions that you can side with (I'd be fine if it was GC based even). You can change, but not so often.
2. People can attack any player of another faction at any given time.
3. No flying in the zone.
4. Have safe zones (like underwater zones that you can jump in and hide in, and sanctuaries that cowards can run to mid-fight).
5. If you party up, you will not be able to attack each other regardless of faction. Easy way to make teams on the fly if you want to.
6. What does SE love? Fates! Have PvP fates with special rewards, and Wolf Marks as rewards as well (and as ppl have suggested for a long while now = make us be able to buy useful stuff with wolf marks). You can screw people over doing those fates as well. There could also be escort fates etc for specific factions where one has to protect a cargo from the other team, or a FATE like the protect the gate one in South Shroud.
7. PVP Beast tribes! This could work as the factions even, doing PvP objectives to gain reputation with the beast tribe.
8. Have certain parts of the zone open up the more you gain ranks or the more you PvP.
9. Have a hub with PvP mini games, in-game tournament, in-game duel organizer, arena.
10. Have certain part of the zone be accessible only when your faction has claimed it. If we want to be stupid, put a rare gathering node in that area where you can for instance gather a new kind of map, Wolf Map, so it keeps being competitive and worth doing.
11. Wolf map. Just maps with gil, wolf marks, new minions and mats etc. Portal that can lead to the "Grand Arena", a King of the Hill like Aquapolis where you climb to get to the master of the Grand Arena. I tried putting a PvP twist on it but couldn't think of any except for that your party can get killed when spawning a map, and the party that killed you can steal the portal. And of course, inside the portal you only have access to your pvp skills and you have to coordinate. Think of the feast but vs PvE "players" (yes, we have Shatter for PvE, but this is just a map).
All of this can give experience as well of course. More than enough here already to make it more fun than a regular zone. If that's not enough to bring people there (who want to try out pvp but are scared of feast and are bored of FL), add Hunts that give Seals and Wolf Marks, and as mentioned, the stupid idea of gathering points. Or you know... just add tomes and materia.