Posted 27 August 2017 - 07:53 AM
The robot is definitely Poseidon as stated above. It is from the Japanese cartoon Getter Robo G. There were three jets that could combine into robots. Which jet took the lead determined which robot they formed. The one you have was the slow/strong one. It also specialized in underwater combat. Getter Robo G was a sequel series to Getter Robo. They were created by Go Nagai, the guy who made Majinga, Grendizer, Devil Man etc.
The toy you have was from a line of 3" mini renditions of popular anime robots of the day. It is most likely from the US licensed versions called Shogun Warriors. There were also larger models with more features. I wouldn't necessarily say it's a bootleg, I have one in the box and the only marking is "Japan".
The head is there, but it is missing a sticker for the face. If you google something like "Shogun Warriors Poseidon" you should be able to find a pic of what the 3" version's face should look like.
Thank you