For Battle Formations, Elements are still matched against each other, only thing that changes is which player fights which match is left up to the teams.
During deckbuilding, along with each player choosing cards from their vault to build their decks, teams would decide which player to send against which opponent... in turn not knowing which player from that element they'd be facing.
Darkness has a Gravity, an Air, a Death, a Time, a Fire, a Light, and a Life this round.
Darkness builds a deck for each of their players: Doc (Master), Grumpy (Lt.), Happy, Sleepy, Bashful, Sneezy, and Dopey
Darkness decides to send Doc vs Fire, Grumpy vs Light, Happy vs Time, Sleepy vs Death, Sneezy vs Life and Dopey vs Air (Battle Formations step).
Each other team does the same thing, so only after you've built your deck and finalized your Battle Formations picks do you find out who you're matched against this round. Simple enough? I'm not sure how else to explain it... maybe it makes no sense and I've gone off the deep end. : P