They might only be small, but in response to fans demanding it for the last three years, Hasbro have created convertible Kreo sets... starting with these four - Optimus, Bumblebee, Starscream, Grimlock.

Each are Gen1-ish, and since they are small, their different modes are a bit kibbley and odd shaped.

But if this is the start of an ongoing line, they should hopefully get better at creating these things with practice.

The official images from SDCC, and the display case at SDCC.
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