Like truly I want an MMO with like the physical engine of Halo because I do good in that game...

And here's my concept for it...

You will create temporary parties with other players and take over cities(not build them). You need to spend points that you get from doing good in PVP to invite people to your group. You also lose PVP points for doing bad. Your group is disbanded if it does bad too. The point of the cities will be to loot periodically refilling nodes inside of them that will only be lootable by those designated by the leader of the city.

The game will be based on a leveling class system. Some classes you will need to unlock for your account by acquiring certain items and attaining a certain level. You level by killing monsters or other players and when you level you unlock new abilities and equipment slots.

Most abilities will function like weapons or grenades. Equipment will affect the damage, healing, buffing, or speed of abilities and general effectiveness of speed and stun abilities. Some equipment will give you special mana bars which will be required for some of your abilities. Many abilities will consume ammo. Some abilities will require you to have certain items equipped to use them. Some abilities create loot nodes. Some abilities will be for crafting. Abilities are either projectiles, melee, or AOE, or auto hit or none or all of the above. Projectiles can spawn more projectiles, AOE, or spawn loot nodes. Abilities and projectiles can also summon mercenaries for you. Abilities can also be either instantaneous, or take up to ten seconds to execute(this ten seconds will be lengthened by taking damage). Some abilities cause you to stop moving or cause you to move. Some abilities will have triggers, meaning like sort of an another ability will happen depending on the outcome of the first ability. You can only have two abilities assigned at one time. Assigning an ability can take minutes or hours. Assigning requires you to stop all movement, damage, abilities and trading. But you can log out while assigning and resume when you log back in.

Not every class will be able to use every item. In fact many items will be made for only certain classes. Some items will only be for specific classes. There will be no inventory but rather your class will unlock new equipment slots and you carry things in these. There will however be guarded trade hubs that can not be taken over, but can still be fought in, where you can store your stuff in banks or use a mailbox or auctionhouse. The banks will be universal and unlimited in size for all of your account.

Some loot nodes will take longer than others. Although you will be able to look at the contents immediately so you know whether or not to spend time looting it which could take minutes or hours of ceasing damage, movement, abilities and trading. It will indicate to you how long it will take to loot. Having a certain class with a higher level or certain items will make some loot nodes able to be looted or able to be looted faster. Again, you can log out and resume looting.

There will be an innocent/criminal/murder system. Where if you attack an innocent player or guard you turn into a criminal for twenty minutes. If you murder an innocent you get a murder count that disappears in 8 hours if you don't kill anyone in 8 hours. Five murder counts and you are officially a murderer. Guards always attack murderers and criminals.

Anyone can loot the equipment of a murderer or criminal without going criminal. But if you loot an innocent body you will become a criminal. IF ONCE YOU HAVE LOOTED THE INNOCENT AND YOU DIE WITHIN TWENTY MINUTES FROM LOOTING... THE INNOCENT PLAYER'S EQUIPMENT WILL BE CONSIDERED ILLEGAL TO LOOT FOR TWENTY MINUTES BY ANYONE BESIDES THE ORIGINAL OWNER OR HIS GROUP(all caps because this has never been implemented in any game and I think its very important to protect the property someone has invested time in and expect a fight for it) Also if the twenty minutes hasn't expired and it is traded then the accepter of the traded item will go criminal. If anyone has possession of an innocent owned flagged good for twenty minutes, then it will no longer drop as flagged for the original owner and illegal for anyone to take. Rather it will require sixty minutes of ownership to be dropped as flagged. Items looted off of anything except for other players will always drop flagged.

Dead bodies from players or monsters will be destroyed by GMs if they're seen to be inactive for a long time with loot that no one wants. Players will respawn with full health.

Groups of players trying to take over a common city will not become criminal for attacking or looting anything off the city group. If you attack someone in a group, you will flag criminal for everyone in the group(unless the group member who you are attacking attacked you first). You can not get murder counts by killing groups. You will flag as criminal for attacking an innocent group member. Players in a group will always be identified by a tag.

Groups of players can loot their members loot without going criminal. If your group member loots your flagged items, these items are automatically considered possessions of the group member.

Criminals and murderers have the right to self defense. Meaning if you attack them first you will flag differently for them and they will not get a murder count for killing you and also will easily be able to identify you as attacking them.

You can even cycle between your character and your mercenaries. Mercenaries have a class just like you. They level up just like you too and each time you summon them retain their level.