By having 60 hits in a season.
Throw a shutout in season mode.
Hit 15 doubles with one player in one season in season mode.
Unlock them in the Monster Locker then use a Hatchery.
U must get 5,000 career receiving yards
You have to get over 300 catching yards in one game
You need to get 5,000 career recieving yards with one player
You upgrade your town hall to lvl 3 and your monster locker to lvl 2
just click on your monster locker then open.choose the monster that you would like to unlock and click UNLOCK.in order to unlock a monster you should have enough putty for it.
play 5 games in season mode and hit 5 home runs no it isn't you unlock him by getting 3 bunt then you hit a home run!
To get Luigi go into the backyard and punch boos. When a cage comes out go towards it and search for a Luigi painting.
To unlock the Inferno base in Backyard Monsters, you need to reach level 50 by upgrading your Town Hall and other important buildings. Once you reach level 50, the Inferno base will be automatically unlocked and available for you to build.
To unlock the Yetis in Backyard Hockey 2005, you must defeat them in a game. Once you win against them, they will become a playable team option for you. They are typically a challenging opponent, so you may need to practice before attempting to defeat them.