What is the PvP system: arenas, open-world PvP, faction wars?

[Xantheo 0]

Please describe the available PvP modes: will there be arenas for team duels, open-world PvP zones, faction/territory wars and sieges?
Clarify the rules for each mode (including penalties/punishments for player kills, new-player protections, PvP flagging), the size and format of battles (number of players), and whether PvP rewards or progression affecting gear/rank will exist. Also, is a separate PvP server planned or will there be an option to disable PvP for characters? 

[Morendal 7]

1) The entire world, except for cities and villages, is an unsafe zone where you can be killed!
2) There are safe duel modes in the world, after which the loser does not lose experience!
3) There are safe arenas—these are safe PvP zones where experience is not lost!
4) For player kills, the killer incurs a penalty and cannot enter cities or use teleportation around the world; if the killer dies, they drop a random portion of their items!
5) Separate servers are not planned; there will be one server for everyone!
6) PvP cannot be disabled!