setblock ~ ~ ~ spawner
scoreboard players set #a lim 4
function bktsb:rng
execute if score #a randr matches 0..1 run data merge block ~ ~ ~ {MaxNearbyEntities: 6s, RequiredPlayerRange: 16s, SpawnCount: 4s, SpawnData: {id: "minecraft:zombie"}, MaxSpawnDelay: 800s, Delay: 500s, SpawnRange: 4s, MinSpawnDelay: 200s, SpawnPotentials: [{Entity: {id: "minecraft:zombie"}, Weight: 1}]}
execute if score #a randr matches 2 run data merge block ~ ~ ~ {MaxNearbyEntities: 6s, RequiredPlayerRange: 16s, SpawnCount: 4s, SpawnData: {id: "minecraft:skeleton"}, MaxSpawnDelay: 800s, Delay: 500s, SpawnRange: 4s, MinSpawnDelay: 200s, SpawnPotentials: [{Entity: {id: "minecraft:skeleton"}, Weight: 1}]}
execute if score #a randr matches 3 run data merge block ~ ~ ~ {MaxNearbyEntities: 6s, RequiredPlayerRange: 16s, SpawnCount: 4s, SpawnData: {id: "minecraft:spider"}, MaxSpawnDelay: 800s, Delay: 500s, SpawnRange: 4s, MinSpawnDelay: 200s, SpawnPotentials: [{Entity: {id: "minecraft:spider"}, Weight: 1}]}