execute unless items entity @s weapon.mainhand iron_sword[minecraft:custom_data~{colosseum_of_fools:{item:soul_nail}}] run scoreboard players add @s jjc_soul 11
scoreboard players set @s[scores={jjc_soul=100..}] jjc_soul 99
scoreboard players set @s[scores={jjc_soul=..-1}] jjc_soul 0
advancement revoke @s only colosseum_of_fools:soul/kill_entity