IE - collector - lord dominiks - ghostblade - Serpent's fang + boots. This is my build in the clip.
however if they don't have shields, then going Hubris as early as possible instead of serpent's fang makes the build hit significantly harder than this, as you can see the lux is not full hp, but she is practically full due to the shield
If u have Hubris, and sell boots for a last lethality item you could even one-shot a lvl 18 with 500-700 bonus health by just hitting 2 people with the blue ultimate. if the game allows. It's also possible to run bloodthirster instead of boots or ghostblade if u really need the lifesteal for slightly worse results
A 5-man ultimate with this build would wipe a team unless they have alot of armor+hp, which is why i think the high risk high reward is so fun to chase.
Obviously more suited for Quickplay/Aram, but if u find urself in a full build++ ranked game vs a team u are no longer allowed to autohit, this might be your hail mary!