I am currently making a boss fight for some of my friends and I can't get the summon command to work and give then entity the right amount of health, even though I use the correct attribute names and such, the command I'm trying to use is this:
/summon minecraft:wither_skeleton ~ ~1 ~ {CustomName:""well_dweller"",CustomNameVisible:1,Glowing:1,Health:300,Attributes:[{Name:"generic.maxHealth",Base:300},{Name:"generic.followRange",Base:103},{Name:"generic.knockbackResistance",Base:0.7f},{Name:"generic.movementSpeed",Base:0.2f},{Name:"generic.attackDamage",Base:4}],HandItems:[{id:"minecraft:iron_sword",tag:{Enchantments:[{id:knockback,lvl:2}]},Count:1},{id:"minecraft:iron_sword",Count:1}],ArmorItems:[{tag:{Enchantments:[{id:protection,lvl:4}]},id:"minecraft:golden_boots",Count:1},{tag:{Enchantments:[{id:protection,lvl:2}]},id:"minecraft:iron_leggings",Count:1},{tag:{Enchantments:[{id:protection,lvl:2}]},id:"minecraft:iron_chestplate",Count:1},{id:"minecraft:player_head",tag:{SkullOwner:MHF_Wither,display:{Name:'{"text":"Well dwellers head"}'}},Count:1}],ArmorDropChances:[0F,0F,0F,2F],ActiveEffects:[{Id:7,Amplifier:24,Duration:100}]}
However, like I said, it won't work. Please help I have to get this finished by tomorrow.