Team Tournaments(2 player teams excluded) have not precise features. A group of players can represent a country, a team or a race. It can aslo be an ad-hoc team. There is usually between three and ten player in a team, matches can be 1v1, 2v2 in different format. Here you can find 3v3 and 4v4 tournaments too.
These are the 10 most recently finished (in the last 9 months) tournaments regardless of tier.