Bosses are powerful opponents that appear every three missions in the Campaign and Campaign+ that are very difficult to defeat and often spawn minor
enemies. There are four bosses in the Campaign: The Tsar Tank, the Zeppelin, the Uber Tank, and the Railgun. A fifth boss appears in Survival Mode, the Armored Rail Tank, but has the ability to respawn. Level 3 turrets are often needed to defeat them.
The first boss of the game, a large tank that resembles a bicycle. It first appears at the end of the tutorial stage and again at Nonne Bosschen Wood (Stage 3).
The "Old Contemptible" achievement is awarded upon its destruction.
The second boss of the game, and notably is the only boss that isn't directly ground-based (not counting RoboBob's final phase in Invasion!). Appears at the end of Fort Douaumont (Stage 6).
Once it bites the dust, you will be awarded the "Flying Pig" achievement.
The third boss of the game, which is a heavily armed tank that is surprisingly mobile. Appears at the end of Battle of the Ancre (Stage 9).
After this boss is destroyed, the "Old Sweat" achievement is awarded.
The final boss of Toy Soldiers, and undeniably the toughest boss of the game if you don't know how to take care of it. Appears at the end of the twelfth and final level, "The Spring Offensive".
As soon as the Rail Gun is no more, the "Coffin Nails" achievement be awarded.
The Armored Rail Tank is a large armored locomotive boss that appears in survival mode.