All-Star Baseball 2000 cheats, and Codes for N64.
At the "Enter Cheats" screen, enter the following codes for the desired effect:
Select exhibition mode and choose Kaufmann Stadium. Then while playing a game, hit one of the signs that say "Win a lizard" to transform all players on the team into lizards. You can also play an exhibition game at Coors field "Colorado Rockies". If you hit a sign in the outfield that says "lizards" on it, your players will turn into lizards.
Big Green Monster
When you are playing a game at Fenway Park, if you hit five home runs over the Big Green Monster (wall) you will become a giant green man.
When pitching in Arcade mode, hold C-Down + A to pitch an fastball that cannot be hit by the batter. Hold it until the ball reaches the plate.
Press Z when running bases and out in the field.