This set of big-headed ゴジラ・ヒーローズ (Gojira-Heroes) is one of my favourites. It's actually the first time that I can tolerate ミニラ!
Here are some badly scanned images of the set, but to buy your own set, you'll have to drop about a 100 bucks! That of course includes the Secret item which is 轟天号とマンダ (Manda which I don't have! It's SOOO sweet!) Without Manda, it's only about 40 dollars, so he must be quite rare! Here in no particular order are the 20 that I have acquired.
My personal favourite is King Caesar. Who's yours and how many can you name?