a soul for a soul
A soul for a soul is when you give up someone else’s soul just to get a soul stone, like when that fat-ass Thanos basically sold his daughter’s soul for a shiny rock so he could be a god and annoy everyone for eternity.
My cousin gave up his soul for a soul stone just to look cool in the game.
That dude gave up his best friend’s soul for a soul stone because he was too lazy to beat the boss.
My mom’s soul was traded for a soul stone so she could play video games nonstop.