Have the ability to re-fight a boss, put like a statue or totem in or somewhere around the fighting area to summon the boss again. The downside is that you get no microplastic and if you die or leave the boss disappears. It would be cool to comeback to a boss and try different builds on them would be a cool challenge instead of replaying the whole game and grind again for one specific build on a boss. Plus it would give those who shot the boss a gun a second chance if they wanna comeback to it and fight without the gun.