Man, this one pulls me back to that arc in 'Saga of the Crestfallen' where the MC gets plopped into a fantasy warzone. The whole sniper-in-an-isekai premise hinges on a contradiction: you've got this tool of extreme, detached precision in a world that often runs on melee chaos and magical area-of-effect nonsense. Your biggest hurdle isn't even hitting the target; it's that after your first shot, every mage in a five-mile radius starts throwing up glowing shields, and every scout with enhanced hearing knows your general quadrant. You're a glass cannon operating on a single, fragile principle of surprise.
Then you have to factor in logistics. Where are you getting your ammo? Is a dwarven smith gonna understand the tolerances needed for a .308 round? And forget about stable platforms—trying to calculate windage when a flight of wyverns just blasted through your perch is a whole new kind of math. The unique challenge, to me, feels less about the shooting and more about the total isolation. You can't hold a line, you can't retreat with the squad. You're a ghost in the machine, and if the machine ever figures out the ghost is there, you're just a very squishy dude in a ghillie suit waiting for a fireball.