This mech is the largest that I have built to date.  I showed it at Bricks by the Bay 2019 where it won an award in the Bionicle category ("Best Humanoid Figure").  This one was built mostly of Bionicle theme parts, though it did have a mix of some Technic and regular system bricks as well.  Notice that the two wings mounted at the rear are two separate large LEGO airplane wing plates.  Using those in a large mech build was among my inspirations for this one.  They were tricky to use in this way because of their considerable weight and size.  It was my goal to get it to stand on its own without assistance of any kind which I was able to achieve in the final design, though it was still very heavy and had to be positioned just right to stay standing.  It actually did end up falling over once during the convention which necessitated a frantic on-site rebuild and repair.