FYI, the rules specify when anyone reaches 0 hp, they are dead. Because characters die so easily with these older rules, many DMs have a house rule that 0 hp results in unconsciousness instead, with some number of negative hp resulting in death. The rule I usually use is when you get to -Constitution score, so for Blackjack, that will be at -10 hp. An enemy will automatically hit an unconscious individual if they attempt it, so if you want to save Blackjack's life, distract those other goblins!
Amethist can cast one Cure Light Wounds spell per day, which restores 1d6+1 hp, but she will need to touch Blackjack with her hands uninterrupted, meaning a goblin can't be attacking her while she casts the spell.
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