To fulfill the 'Play a game online' stat, you simply have to select 'online' in game modes, and it just gives you the points. That's it, it doesn't even check if you have a network adaptor installed, and it's an easy way to get 4000 credits.
When playing in NFL Challenge mode, enter a medal challenge where you can get either a Gold, Silver or Bronze. For example, go to the Sportsplex field (the baseball field) and go all the way down to the last challenge. It should say "Sack the QB three times in this play". After you complete the challenge, it should say: "You won [number] of development points", and have the choice to exit or retry the challenge. Choose "Retry Challenge". Keep doing this for however many times desired. When you go back to the main NFL Challenge menu, you will see that all the times you won the challenge, you kept the development points you won. If you did this a lot, you will have a large number of development points to spend on your players.
If you have a save for any of the following saves on your memory card, you get an extra 25000 credits PER GAME when you start the game. Need for Speed Underground 2, NCAA Football 2005, NFL Madden 2005, NFL Street, SSX3.
Import Character Into Madden 2006 - Complete Own The City
Import Character To NFL Challenge Team - Complete Own The City
To unlock Team Xzibit, complete the entire Tutorial and you will get Team Xzibit, and a bunch of credits as well.
Perform a "Hot Spot Play" on each field to unlock the respective hidden NFL legend. There are 11 unlockables in all. Below is a list of which players are unlocked on each field.
Mike Singletary - Second St. Station
Randell Cunningham - Imperial Tower
Bo Jackson - Sportsplex
Anthony Munoz - The Cage
Mean Joe Greene - The Tracks
Chris Carter - The Alley
Jack Lambert - Royal Park
Joey Browner - The Dig
Sterling Sharpe - The Aqueduct
Darrell Green - The Backlot
NFL Legends - Team EA Field
Gridiron Park - Complete NFL Gauntlet
NFL Legends - Beat NFL Legends in Own the City
Alternate Way to Unlock NFL Legends - In quick game hit every hotspot at every level to unlock NFL Legends.
Enter "XxGBCraZ" as a case-sensitive code.
At the main menu go into options, then go down to the codes and type it in.
Unlocks EA Field - EAField
NFC South All-Stars - SNOFUCTH
NFC East All-Stars - NNOFRCTH
NFC West All-Stars - ENASFSCT
AFC South All-Stars - SAOFUCTH
AFC North All-Stars - NAOFRCTH
AFC East All-Stars - EAASFSCT
AFC West All-Stars - WAEFSCT
Team Reebok - Reebok
No Fumbles - GlueHands
NFC North All-Stars - NNAS66784
Get rid of the chains! (no first downs) - NoChains
Unlocks Team Exzibit - TeamXzibit
All players will have a maxed out catching stat - MagnetHands
Unlimited Turbo - NozBoost
Other team fumbles a lot - GreasedPig
Unlocks Gridiron Park - GRIDIRONPRK
Enter "str2mkryz" as a case-sensitive code to unlock the Gridiron field and NFL Legends team.
Enter GlueHands as a cheat to never fumble.
Enter WAEFSCT to unlock AFC west all star team.
Enter Reebok as a cheat to unlock team Reebok.
Enter TeamXzibit as a cheat to play as team xzibit.
Enter EAfield as a cheat to play at EA field.