See The Credits - At the title screen, hold A + B and press Start.

Play Namco vs Namco - Start a 1 Player game, pick "N Team" (Namco Team) and enter "CC70" as the password. You'll go head to head with the N Team too.

Atlanta vs Tengen - 6653UJNU

Boston vs. Tengen - JOOMB6AP

California vs. Tengen - SUOMB6AP

Cleveland vs. Tengen - VOOMB6AP

Detroit vs. Tengen - ROOMB6AP

Minnesota vs. Tengen - SIOMB6AP

Oakland vs. Tengen - SEOMB6AP

Seattle vs. Tengen - SAOMB6AP