1) One or more players are the Borg. These are the seekers and have to assimilate (find) everyone else. The number of Borg is determined by the total number of players. Use your best judgment.
2) The Borg will count to whatever number (10, 20, etc.) to give everyone else time to hide.
3) Everyone picks a place to hide and they can move around if they want using any means necessary. When a Borg sees one of them they let the person know and the person has to stay where they are. The Borg goes up to the person, announces the find in chat and assimilates this person.
4) This new Borg has to help search for the other players.
5) The winning player is the last one who hasn't been found. So if there are 5 hiders and 4 have been found, the 5th one is the winner.
The game is long and hard enough as it is, but if you want to make things a little harder you can do this.
6) One of the Borg is designated as the Borg Queen who will always be a seeker and when the Queen finds someone, that player is automatically assimilated.
7) When other Borg find someone both players roll dice. If the Borg has a higher number, the person is assimilated. If the hider has a higher number the Borg is freed from the collective and can hide again. Make sure it is announced in chat.
One player can be designated as a rescuer and a small area of the map can be designated the safe zone. After a predetermined period of time (for example 10 minutes), the rescuer can begin searching for the other players.
When the rescuer finds another player he/she has to escort that player to the safe zone. A rescuer can only rescue one player at a time. Players are not allowed to go to the safe zone alone, they must be escorted.
The rescuer does not have to stop moving if spotted by a Borg. Neither does the player who is being escorted; however if a Borg does catch up to them then they are assimilated. When a rescuer is assimilated another player can be designated as the new rescuer.