MLB SlugFest 2006 - Unlock Martians

Fireball:
When you're pitching chose a fastball. It doesnt matter where you place the pitch. When your pitcher is in the middle of his windup, tap X repeatedly. This will create the fireball trick pitch.

Unlock Pony Team:
Do a take-out slide at home plate.

Unlock Rodeo Clowns:
Get a double play.

Unlock Team Bobblehead:
To unlock Team Bobblehead you have to hit 10 homers with one team.
note: you need to hit all 10 in one game.

Unlock Lions:
Hit a homer with Tigers in Comerica Park.

Pinto:
To unlock the Pinto's, you need to hit an ITPH Inside The Park Homerun at Busch Stadium. To get to stadium select, pick the team you want to be and the team you want to play against. then when the screen pops up that says PLAY, scroll down a little to select stadium, click on it. Then scroll around the map untill you find BUSCH stadium. That is how you unlock the Pinto

Bonus Stadiums:
Atlantis - Hit a homerun in AT&T Park.
Coliseum - Hit a homerun in Fenway Park.
Empire - Hit a homerun in Yankee Stadium.
Forbidden City - Hit a homerun in PetCo Park.
Rocket Park - Hit a homerun in Minute Made Park.