Team Aqua is the organization that Archie has created in order to awaken Kyogre. Archie and Team Aqua's goals are to awaken Kyogre in order to expand the oceans in the world.
Team Aqua and Team Magma have been against each other since Maxie and Archie parted ways those years ago.
Team Aqua has many hundreds of members, two admins, and their leader Archie. Between them you will find a variety of water, ice, and dark pokemon, as well as many Golbat, Crobat, and Mighthyena. They also have a spy network throughout Hoenn and have a stronger prescence in coastal cities and islands.