From the Game's Website:

"NFL Adrenalyn XL by Panini is the all-new trading card game developed to introduce fans to the hobby of card collecting. This easy-to-learn card game captures all the fast-paced excitement of the National Football League and puts you in control. Build your ultimate fantasy team and dominate your opponents with stars like Peyton Manning, Drew Brees, Tim Tebow, Adrian Peterson.

Game Play

Each of the five starters on Offense and Defense can be used only once per set of downs, with the exception of the Quarterback on Offense.

All cards must participate in a play before you can reuse them, with the exception of the quarterback. Even in the event of a first down, cards cannot be reused until each has participated in a play.

Play Calling: Next, the Offense announces their play call: Run or Pass. Run plays use only one starter, while Pass plays involve two starters (Quarterback plus another player).
The Defense is allowed to "boost" the Defense Run or Pass Rating of the selected card by combining that number with the Star Rating of a second card. The Defense may "boost" just ONE play per set of downs.

After the cards have been selected, the Offense and Defense reveal their players and the outcome of the play is determined by the ratings.

Run Plays: Compare the Offense Run Rating and the Defense Run Rating. The difference of the two determines the yardage. For example, if the Offense is 50 and the Defense is 41, the Run gains nine yards. If the defense uses its "boost" on this play and the "boost" rating was six, then the new Defense rating is 47 the rush gains only three yards instead.

Pass Plays: Add the Quarterback Pass Rating and the Pass Rating of the selected player. Take that total, and compare it to the Defense Pass Rating. The difference of the two determines the yardage. For example, if the Quarterback Pass Rating is 30 and the selected Offense Player is also 30, for a total of 60, and the Defense Pass Rating is 50, the Pass gains 10 yards. If the defense uses its "boost" on this play, and the "boost" rating was five, the pass gains five yards instead.

Substitutions: Teams may substitute players only at halftime. However, they can use the same starters throughout the game.

Overtime: If the teams are tied after four quarters, a new coin flip will determine who has the first possession of overtime. The first team to score wins the game."

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