>>537244796
Did you build it? If you do, mentioning the complexity of the build could help, because 16-20 cm sounds like 1/100 scale, but there's master grades (of which there is a more limited pool) but also because there are 1/100 kits that aren't quite as engineered as MG, but are of a different scale from HG. That time period immediately rules out AGE onwards (the picture you posted is from AGE), while Unicorn could still be a possibility if you were misremembering the time period as being earlier than it actually was. It does make it more likely that it's something from 00, since that came out like 2007 and it has designs that are reminiscent of the AGE designs. I'm not sure if this is what you've already done, but you can look at a list of all the master grades released by year and see if you can recognize it from the list. If it's not there, there's still the possibility that it's a 1/100 kit that doesn't have a grade.