If you won your match 3-0 and are a Defender, you have successfully stolen some of the Invaders' advanced technology. This allows everyone in your team the option to use a certain amount of upgraded cards in their decks for the remainder of the event. This number is defined by the total number of points you have divided by 3. You are now alloted one player swap, which allows you to swap any one Defender for any one Invader, both of your choosing.
Why an unnecessarily complicated system like that? The most logical way to do the technology stealing is clearly players stealing ALL the high technology that the opponent used during the battle. So if the invader used 6 upped cards, then the defender will steal those same 6 upped cards. If the invader used 3, the defender steal 3. Simple.
That system works the best because invaders have to really think about how many upped cards they want to use. If they get greedy and take too many, a loss could be devastating.
About that last part.. why is it needed? Problem with swaps like that is the fact that there's a need for extra step of communication. Instead of organizer doing the seeding and battles starting straight away, we now have an extra phase of discussing about who replaces who, and then informing the opponent and organizers about it.
