Steal Reworked Caitlyn's cupcake late game, and she can one-shot you from 1600 units away.

Headshot now scales with crit chance and crit damage, for up to 200% TAD bonus damage, while the auto attack itself can still crit for 250% TAD (with IE) like usual, for 450% TAD damage total

When someone steps on Cait's trap, she can get a free headshot on them from doubled range, and that headshot does 10% to 50% multiplicative bonus damage, based on level.

There is a new item that builds up like shiv, called Rapid Firecannon, that adds 150 range to the empowered auto attacks, and adds 50-200 bonus damage to that auto attack, based on level. I'm unsure exactly how it interacts with her range doubling on trapped units. WIth this charged, her range goes to 800, so I'm just assuming her traps functions as worded and double it to 1600.

With a fairly standard build of Essence reaver, IE, SS, and Rapid Firecannon, at level 18, this comes down to ((450% TAD) +(375 magic damage from SS + 200 magic damage from Rapid Firecannon)) x 1.5 from trap =** 675% TAD physical damage + 862.5 Magic damage.**

I believe her AD is 94.9 at level 18. Let's assume she's getting 6.75 AD from quints, and 10 from masteries. Essence reaver gives 65 AD, as does IE. She's getting 40 more AD from a last whisper item, and another 30 from red pot. 94.9+6.75+10+65+65+40+30 = 311.65 TAD

311.65 TAD x 6.75 = 2103.6375 physical damage. 2104 Physical damage + 862 Magic damage = 2966 Total Damage. BOOM, headshot.

This is absolutely a best case scenario (although she coulda sold boots for BT for another 469 damage), but it is one that we will occasionally see. It certainly has counterplay - don't step on the trap. I've seen this happen in bots, but I've yet to see it in PvP.