Inside the undercarriage, there are several cogs. These range from levels one to twelve and can be skelecogs. Cogs appear to be smaller when they are inside the undercarriage. They come outside one by one to attack toons on both sides until all of the cogs or toons are defeated. As they come outside, they will enlarge and take their place in battle. Each boss has different kinds of undercarriage cogs:
The Vice President has two cog rounds. In the first round, normal cogs, ranging from levels one to twelve, come outside. There will always be a level twelve Mr. Hollywood in the first wave. In the second round, the cogs are skelecogs. They range from levels four to twelve. Just like the first round, there will always be a level twelve skelecog coming out first.
The Chief Financial Officer only has one round of cogs, but they take longer to defeat than both of the VP rounds combined. Normal cogs will range from levels one to twelve and skelecogs are levels seven to twelve. Similar to the other boss battles, the first cog will always be a level twelve Robber Baron (can be either skelecog or normal).
The Chief Justice also only has one cog round, but it is even harder than the CFO's cogs. All of these cogs are normal cogs, but they are at least level eight. Similar to other boss battles, the first cog will always be a level twelve Big Wig.
In the boss fights, the VP and the CFO will use their undercarriages for other benefits as well.
- Main article: Undercarriage gears
In the second round, the VP opens up either one of its undercarriage doors to throw out gears. These gears cause toons to lose two laff points if they hit. This attack, however, backfires at the VP. After opening its undercarriage, toons can throw pies into it and stun him. Doing so is necessary to win the battle.
- Main article: Goon
In the second round, the CFO opens up either one of its undercarriage doors to let a goon walk out. The goon's size, color, and damage is based on the CFO's health. The goons can be disabled with a stomp and can be picked up with one of the magnetic cranes. Then it can be thrown at the CFO to destroy the goon and hurt the CFO. They can also be destroyed if it initially walks into a safe or a safe is thrown onto it.