Mine would have to be AM Circuit.

When I was in year 11 of high school and still heavily into Transformers, I sold some of my Star Wars figures to another kid at school for some extra cash knowing that we were all going on an excursion to the city.

I bought Circuit and stashed him away in my school bag to sneak him into the house concerned about what my parents would think of their son still buying 'toys'.

I only bought him because a lack of choice that the store had. Being my first AM, I found the toy to be very underwhelming. In my role playing, he was always the first to die