tag @s add PlayerNearby

execute as @s[tag=!FirstContact] run execute if entity @a[distance=..25,gamemode=!spectator] run function zzzzdonotuse:biomecorruption/blackcorruption/firstcontact

scoreboard players add @s[tag=!DoAttack] KyuDummy 1
execute as @s[scores={KyuDummy=3..}] run function zzzzdonotuse:biomecorruption/blackcorruption/shulkerattack