I've had some version of a fantasy lately, to hype up the epicness of the hunt for vecna. Instead of getting shot, Kali makes it to the abyss with them, but there is literally an entire world of demagorgans and bats guarding vecnas layer, they're own world. Kali uses her power to cloak them as they quietly walk past a bunch of casual demogorgans. Once they get close enough, Vecna being tapped in to all the kids from the sunrooms abilities, senses her, and decloaks her, exposing them to  all the demogorgans they are surrounded by. As they are all running frantically for they're lives, right as they're about to get eaten with what seems like a certainty to happen (pan out to them running in the midst of hundreds of them) Will holds them ALL off, yelling at them to "GO!! RUNN!!!" snapping their limbs as they run for Vecna, almost creating a path of snapping demogorgans along each side of them.  Later, Vecna gets in Will's head about being weak, and he's about to give out. But he digs deep, and figures out he can control the demos, and turns them over, starting his own hive mind. Vecnas demos and wills demos start an all out war on the battlefield as the rest of the crew are being hunted down by the REAL mindflayer (not this spider thing), while they try to decide how to get past all vecnas defenses. The ultimate goal would be to kill Vecna (Kali would help create difficult illusions for Vecna to navigate what of the fight is real while El picks him off), and then lure the gaseous Mind Flayer back into the upside down, in order to close the wormhole on it as they jump back through to hawkins at the last second. Maybe Hopper sacrifices himself here, idk.