Yes, Player B nonetheless takes injury from the Goblin Fireslinger. Rule 112 covers this adequately. Rule 112.3a tells us that Activating a capability places it on the stack, till it resolves, is countered (Stifle), or it in any other case leaves the stack (Time Stop). Rule 112.7a tells us that the activated potential exists impartial of the supply, and doesn’t high quality this separation with objects shifting to a hidden zone.

112.3b Activated skills have a value and an impact. They are written as “[Cost]: [Effect.] [Activation instructions (if any).]” A participant might activate such a capability each time she or he has precedence. Doing so places it on the stack, the place it stays till it’s countered, it resolves, or it in any other case leaves the stack. See rule 602, “Activating Activated Abilities.”

112.7a Once activated or triggered, a capability exists on the stack independently of its supply. Destruction or removing of the supply after that point gained’t have an effect on the flexibility.

It is feasible that they’re complicated this with the foundations relating to monitoring objects which can be shifting between zones. Normally, objects don’t have any reminiscence of their earlier existence in one other zone, and grow to be new objects. There are 7 exceptions, and (d/g) are in all probability those that they’re complicated this with. These exceptions exist, as a result of playing cards like Rancor exist that have to have guidelines that permit the playing cards to truly work.

400.7. An object that strikes from one zone to a different turns into a brand new object with no reminiscence of, or relation to, its earlier existence. There are seven exceptions to this rule:

400.7d Abilities that set off when an object strikes from one zone to a different (for instance, “When Rancor is put into a graveyard from the battlefield”) can discover the brand new object that it turned within the zone it moved to when the flexibility triggered, if that zone is a public zone.

400.7g A resolving spell or activated potential can carry out actions on an object that moved from one zone to a different whereas that spell was being forged or that potential was being activated, if that object moved to a public zone.