Here is the full list of all 17 Toy Soldiers achievements.
Defeat the K-Wagen
Defeat RoboBob
Survive until Round 5
Shoot down 40 UFOs with your P-51 Mustang
Complete the Campaign
Complete any level in Elite mode
Guide a shell to its destination
Defeat Uber Tank
Defeat Zeppelin
Earn General Rank on any level
Defeat Tsar Tank
Complete level 1
Earn General Rank on all Campaign levels
Complete Campaign+ and earn all Ration Tickets
Find all of the golden cubes in The Kaiser's Battle
Get a 40x blast combo
Find all of the golden rockets in Invasion