Sandlot Sluggers

The last level in the game, this isn't at all difficult even though the game might make you think otherwise. You'll have the all-star team by this point and if you just hold Up+B whenever you bat you should be hitting homer after homer. I was easily up 12-0 after one inning, and mercy ruled his team from there.

The bullies team is good, but your team is so much better it's actually ridiculous. It doesn't hurt that it's one of the easiest parks to hit home runs in. After beating them, you've won the game and this achievement.