Shoulder

'Cold shoulder' indeed.

The shoulder is one of the most vital components of a Transformer's body.

It is unknown why the shoulder is such an Achilles heel of Cybertronians. However, it is clearly the most easily damaged location on their chassis, as many instances of minor damage have led to grave injury and even death.

Such instances include:

• In a battle on Earth, Ironhide was shot in his shoulder by Megatron. Seeing this injury, Optimus Prime immediately called off the attack to get Ironhide immediate medical attention.
• Years later, the incredibly strong Autobot Brawn was killed in a single blow from a wound to the shoulder. TFTM
• Catilla was killed by a blow to the shoulder from Bludgeon's sword. A Savage Place

There are very likely many more examples of shoulder wounds and their fatal nature. The only theory is that many Transformers store their Spark in their shoulders.

Known toys to have Sparks in the shoulders

Beast Wars

• Scourge
• Spittor (Transmetal 2 version)
• Stinkbomb

Beast Wars Neo

• Dead End
• Magmatron (one of the sparks anyway)

Beast Machines

• Cheetor (Mega and Supreme)
• Beast Changer
• Blast Punch Optimus Primal

Robots in Disguise/Car Robots

• Gas Skunk
• Slapper

Energon

• Beachcomber
• Cliffjumper
• Downshift
• Inferno
• Megatron/Galvatron (All versions)
• Optimus Prime (Deluxe and main line Leader Class)
• Overcast
• Roadblock
• Shockblast
• Six Shot
• Tow-Line

Universe

• Downshift

Other

• Ironhide (Descent into Evil)
• Ratchet (Descent into Evil)
• Megatron (Shattered Glass)