Only thing really needed is the right attitude. Teamplaying is about attitude and wanting to play together. If a player hunts kills and his own goals he is not a teamplayer. Me and Eren buddy up often and kick ass because I always protect him the best way I can and he plays smartly. To me it's far more fun to have a goal in a game than hunt kills. Keeping a skilled player alive gets me multi also. I often protect Mercs and other quality players who play smartly and don't get killed. Sadly there are only a few good players alive who also work together without the need of teamspeak.
CRPG is full of individuals. Some want to play their thing/class. Some do want teamplay at least in some level, but lack clan or a leader to follow. Only a few are truly dedicated teamplayers. 95% of the players fight alone and oblivious to their surroundings.
I remember a year or two ago or so when Pecores often played as a team and often totally owned the server. They are a shadow these days tho. They didn't fight as a tight formation. They however moved together and the attacked as an aggressive horde. Good players + heavy armor + shields + aggressive style got the victory often.
