Ugh. I just had a horrible flashback to my first mmo. The entire thing was centered around having to group with people. Exp rates were atrocious, but you got a 5% bonus for each person in your group in the zone. Some moves could only be performed if you had a group. For instance a priest move gave your group holy armor, reducing damage taken from demon, undead, and shadow type monsters. But the casting priest had to have 2 other priests standing next to him to cast it, or the move wouldn't work. One class, the soul-linker, had 0 ability whatsoever to fight for itself. Every move it had was a 'link' spell, one for each class in the game, that gave the other players an often completely brokenly overpowered buff, like perma bloodlust haste.