We have an almost full set of these alphabet letters that convert into robots. I found one additional letter (V, I think) since I took this photo, so it's just the letter K that's missing. They can also be assembled into one large robot, but you'd need to google around to find the instructions.
https://www.lakeshorelearning.com/products/ca/p/AC225/
Alphabet Robot toys (Near Backestro Park, San Jose)
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