just put in your command block then activate. you will need armor and weapons.



command: 


/summon Ghast ~ ~1 ~ {CustomName:"FAT GHOST [-'_'-]",CustomNameVisible:1,Attributes:[{Name:"generic.maxHealth",Base:2147483647},{Name:"generic.followRange",Base:500}],ExplosionPower:2,DropChances:[2F,2F,2F,0F,0F],Equipment:[{id:"minecraft:beacon",tag:{display:{Name:"Heart Of Ghost",Lore:"Shiny..."]}},Count:1},{id:"minecraft:iron_ingot",tag:{display:{Name:"Ghost Skin",Lore:["Ugh, it's the head... -'_'-]"]}},Count:1},{id:"minecraft:soul_sand",tag:{display:{Name:"--",Lore:["AGDUNUWQNDUQWNU9QD2H72165345D79A8H2NDISA7Q52Q7W87DUDWJUB1S8Q9WD8E5Q67QWG27DES87TDQ78WGQWD{O_O}TF87QG81`FT7SHQ"]}},Count:1},{},{}],ActiveEffects:[{Id:5,Amplifier:1,Duration:2147483647,ShowParticles:0b}]}





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