A battle tank suitable for 28mm wargaming like for example Grimdark Future: https://onepagerules.com/portfolio/grimdark-future/.
Basic Chassis: InnerIn, ChainsInner, SideBetween, SideOut. Print everything twice and mirrored and Chains inner four times. Glue together the top side of InnerIn and the bottom flat side of ChainsInner. Now connect these by placing SideBetween between them and SideOut on the outside.