Age of Extinction film
After Galvatron took control of all the KSI prototypes, the army of new Decepticons including multiple Two-Head units, descend upon Hong Kong. Hound goes one-on-one with one of them who succeeds in tackling him to the ground, Hound then proceeds to flip around the cigar in his mouth, which turns out to be a live shell, and bites down on it causing it to go off and shoot the Two-Head through one of its heads, killing it.
Later on, a Two-head is seen pointing towards Optimus, along with several other Prototypes. However, he is killed by Lockdowns grenade, which Optimus set off.
After Lockdown is destroyed, it is unclear what happens to him or the other surviving KSI Decepticons.
- The "Shockwaves" with multiple heads could be a subtle reference to how he was taken out in the previous movie. In DOTM, Shockwave went down when the humans were able to destroy his single eye, leaving him blinded and incapacitated. During the intro for Stinger, it's mentioned that the idea behind the prototypes was to take the design of the original Transformer (in that case, Bumblebee) and improve it. How to improve Shockwave's design? Give him multiple heads, so if someone destroys the eye in one head, he won't end up blinded and helpless because the eyes in his other heads will remain functional. 
- ↑ Originally posted by El Zilcho of the TFW2005 boards (http://www.tfw2005.com/boards/transformers-movie-discussion/986229-errors-jokes-references-hard-spot-things-aoe-6.html).