Team Constructed tournaments use Unified Deck Construction rules: Except for cards with the basic supertype, no two decks on a team may contain the same card, based on its English card title. (For example, if one player is using Naturalize in a Team Constructed tournament, no other player on that team may use Naturalize in their deck.) No players may use cards that are banned in a particular format. Cards that override deck construction rules (i.e. Relentless Rats, Shadowborn Apostle, etc) may only override them for one deck on a team.
Unified Deck Construction rules are only applied when all members of a team have decks of the same format.