Here is the full list of all 16 Baseball Riot achievements.
Earn at least two stars from each level in region 2.
Knock everyone out with the first swing in a single level in region 2. Explosions don't count.
Knock out 5 enemies with a single swing in region 1.
Earn at least two extra balls during one level in region 1.
Get five headshots with a single swing in region 3.
Swing a ball that bounces 100 times in region 3.
Knock out six enemies with a single Explodz explosion in region 4.
Destroy 10 pieces of glass during one level in region 4.
Collect four extra balls during one level in region 5.
Destroy three vending machines with a ball and a single swing in region 5.
Complete a level with a single swing while collecting all stars in region 6.
Collect three stars from every level in region 6.
Collect three briefcases with a single swing in region 7.
Knock out four scientists with a single swing in region 7.
Knock out all enemies in a level with the first swing and only with headshots in region 8.
Get a region score of 40 points or higher in region 8.