The aim is to present the runner with a 50/50 choice stacked in your favour. You do this by playing mushin and then advancing for a fourth counter. If they run junebug then you win. If they leave a vanity then you win. If they correctly run a vanity (or leave a junebug) then you get to rinse and repeat.
Being able to play the gambit twice is pretty important (it pushes you up to a 75% win ratio!) so every other card is aimed towards helping you to stabilise early and thus ensure that you get two bites at the apple.
Clone Sausages (each is as delicious as the last), TFP, The Toyman and a low agenda density make it easy for you to close out the game but hard for the runner to find non-gambit agendas. Batty and the ICE suite are there to tax or kill early runners and the econ is more than strong enough to do everything you want to do.
At this point I'd love to say "the jank is for realz". Unfortunately Diesel and On The Lam both exist and are popular includes. Alongside a bunch of much less standard cards (Fisk Investment, Drive By, Romp) these probably stop the concept from ever becoming competitive. On The Lam is a particularly big kick in the teeth (since it blocks the cerebral overwriter variant). Fortunately these cards aren't a direct counter so it is still a fun deck to spring on the unsuspecting.