Glass Hovercar Medic
I have this tier 4 medic hovercar with most of the body made of windshield parts, mostly cause anything better would take it into tier 5, but i choose windshield blocks over white blocks for the looks.
It has 3 tier 6 nano's so i heal most tier 4 robots from 10% to full health in a matter of seconds.
Even though this is a very effective build, it's also pretty weak. Though, most of the time i don't get hit cause i'm too agile :P
Some other details: 8x steering wheels T2, 10x hoverblades T3, T3 mounts for the guns, t2-t6 rainbow underneath and 8x thrusters t1-t4 (dunno amount)
If i upgrade anything, even add a single white prism, the bot goes into tier 5 but i like to keep it in tier 4.