Simple Halloween Event For Your Server

Just build 3 (or more) pumpkin patches, place a command block and paste these codes in.  The Witch is easy to kill, The zombie is a bit harder, and the skeleton is the hardest. Skeleton drops a Modified bow and a blaze mask, zombie drops a modified axe and a spider mask, and the witch drops the ghast mask. All with a 10% drop rate.

2015 Blaze Mask:

/setblock ~0 ~1 ~0 mob_spawner 0 replace {SpawnCount:1,SpawnRange:3,maxNearbyEntities:1,Delay:20,MinSpawnDelay:3000,MaxSpawnDelay:6000,EntityId:Skeleton,SpawnData:{Equipment:[{Count:1,id:bow,tag:{display:{Name:Jack Skellingtons Bow,Lore:A Finley Crafted Bow Made From Bones]},ench:[{id:50,lvl:1},{id:48,lvl:1},{id:49,lvl:1}]}},{id:chainmail_boots,tag:{ench:[{id:4,lvl:3}]}},{id:chainmail_leggings,tag:{ench:[{id:0,lvl:3}]}},{id:chainmail_chestplate,tag:{ench:[{id:0,lvl:3},{id:7,lvl:3}]}},{Count:1,id:skull,Damage:3,tag:{SkullOwner:MHF_Blaze,display:{Name:A Blaze Mask,Lore:[Halloween 2015]}}}],CustomName:Jack Skellington,CustomNameVisible:1,DropChances:[0.1F,0.0F,0.0F,0.0F,0.1F],PersistenceRequired:1,SkeletonType:1}}

2015 Spider Mask:

/setblock ~0 ~1 ~0 mob_spawner 0 replace {SpawnCount:1,SpawnRange:4,maxNearbyEntities:2,Delay:20,MinSpawnDelay:1500,MaxSpawnDelay:3000,EntityId:Zombie,SpawnData:{Equipment:[{Count:1,id:iron_axe,tag:{display:{Name:The Head Chopper,Lore:HelloCraft Halloween 2015]},ench:[{id:35,lvl:2}]}},{id:chainmail_boots},{id:chainmail_leggings},{id:chainmail_chestplate},{id:skull,Damage:3,tag:{SkullOwner:MHF_CaveSpider,display:{Name:A Cave Spider Mask,Lore:[Halloween 2015]}}}],CustomName:A Wicked Zombie,CustomNameVisible:1,DropChances:[0.1F,0.0F,0.0F,0.0F,0.0F],PersistenceRequired:1,IsVillager:1}}

2015 Ghast Mask:

/setblock ~0 ~1 ~0 mob_spawner 0 replace {SpawnCount:1,SpawnRange:4,maxNearbyEntities:2,Delay:20,MinSpawnDelay:1500,MaxSpawnDelay:3000,EntityId:Witch,SpawnData:{Equipment:[{},{id:chainmail_boots},{id:chainmail_leggings},{id:chainmail_chestplate},{Count:1,id:skull,Damage:3,tag:{SkullOwner:MHF_Ghast,display:{Name:A Ghast Mask,Lore:Halloween 2015]}}}],CustomName:A Wicked Witch,CustomNameVisible:1,DropChances:[0.0F,0.0F,0.0F,0.0F,0.1F],ActiveEffects:[{Id:22,Amplifier:1,Duration:999999}],PersistenceRequired:1}}

Masks are dated 2015, you can edit the code to drop whatever mask you want, and change the name and lore as well

I also set up villager that sells normal heads, zombie, wither skeleton, creeper & skeleton. yo have to buy them with rotten flesh, 100 per mask, here is the code for that too:

/summon Villager ~ ~1 ~ {Invulnerable:1,CustomName:Basic Halloween Mask Vendor,Profession:1,Career:1,CareerLevel:6,Offers:{Recipes:[
{buy:{id:367,Count:50},buyB:{id:367,Count:50},sell:{id:397,Count:1}},
{buy:{id:367,Count:50},buyB:{id:367,Count:50},sell:{id:397,Damage:1,Count:1}},
{buy:{id:367,Count:50},buyB:{id:367,Count:50},sell:{id:397,Damage:2,Count:1}},
{buy:{id:367,Count:50},buyB:{id:367,Count:50},sell:{id:397,Damage:4,Count:1}}]}}

Happy Halloween!