Mirror Tech, Online
Research an upgrade, and a few waves later it's pointed right back at you.
The signature mechanic went live: Mirror Tech. Every tech you unlock, MONARCH reverse-engineers and hands to its machines a few waves later. Punch up your turret rounds, and soon the Hunters have armor rated for exactly that.
It turns the tech tree into a gamble instead of a checklist — go tall and you're strong now but you arm the enemy sooner; go wide and you stay ahead but launch slower. You are, functionally, in an arms race with a mirror.
STATUS: two intelligences, one tech tree. Better machinist wins.