This is a pitch idea, for University, but i was mostly focusing on concepts and my UI work.
The game is a first person mmo, which gives players the freedom to travel across three different worlds and allows them to play it with who they want to play it with.
Using the light and dark progression system they are able to traverse worlds through actions. based on player to player interaction. Trading or giving players items maybe considered a good deed, attacking players in the world will be considered a bad deed, (note you can't attack players in the hub world).
The portal on islands and the hubs will allow you to return to an area you have previously discovered.
There will be pvp (player vs player), Pve (player vs enemy) within the world, there will be raids/dungeons.
The arena mode will have weapons as there core, so sword, spear, bow etc. no levels/gear progression on weapons and armour to make it balanced. (see image PVP)