/summon with NBT: equipment, attributes and the tags that make a mob behave
Summoning a mob is one word. Making it keep its gear, not despawn, not burn and not wander off takes six specific tags. Here is what each one does.
/summon zombie works. A zombie that keeps its armour, stands still, survives daylight and never despawns needs six more tags, and they are not discoverable from the command help.
The six that matter
/summon zombie ~ ~ ~ {PersistenceRequired:1b,NoAI:1b,Silent:1b,Invulnerable:1b,
CustomName:"Guard",CustomNameVisible:1b}| Tag | Effect |
|---|---|
PersistenceRequired:1b | Never despawns. The single most important one for map-making |
NoAI:1b | Frozen — no movement, no attacks, no gravity |
NoGravity:1b | Floats, but keeps its AI |
Silent:1b | No mob sounds |
Invulnerable:1b | Immune to everything except /kill, the void and a creative-mode player |
Glowing:1b | Outline through walls |
PersistenceRequired and naming are related but not the same: a name tag also prevents despawn, but CustomName set via NBT does not unless you add PersistenceRequired. That trips up nearly everyone building a shop NPC.
Equipment that does not drop
{equipment:{mainhand:{id:"minecraft:diamond_sword",count:1},
head:{id:"minecraft:diamond_helmet",count:1}},
drop_chances:{mainhand:0f,head:0f}}Equipment is a map keyed by slot name — mainhand, offhand, head, chest, legs, feet, body, saddle — so there is no slot order to get wrong and no empty placeholders: list only the slots you fill. Older guides use HandItems and ArmorItems arrays (ordered feet, legs, chest, head), which 1.21.5 replaced; they no longer do anything.
Drop chances are floats per slot in drop_chances, from 0f to 1f. Anything above 1f guarantees the drop and keeps the item's enchantments and durability intact.
Attributes
{attributes:[{id:"minecraft:max_health",base:40},
{id:"minecraft:movement_speed",base:0.35}]}Setting max_health in the same NBT also spawns the mob at that full health — Health defaults to the new maximum. Only add Health:…f when you want it to spawn damaged.
Common ids: max_health, movement_speed, attack_damage, armor, knockback_resistance, follow_range, scale.
Passengers stack downward
{Passengers:[{id:"minecraft:skeleton",Passengers:[{id:"minecraft:chicken"}]}]}The outermost entity is the one at the bottom. Nesting Passengers inside Passengers builds the tower upward. Each rider needs its own full NBT if you want it configured.
Bedrock is different
Bedrock has no NBT argument on /summon. The syntax is /summon <entity> <pos> <yRot> <xRot> <spawnEvent> <name>, and behaviour is set through spawn events rather than tags. A Java NBT blob pasted into Bedrock will not run.
Pick a mob and toggle these tags visually — with the armour slot order handled for you — in the /summon Generator.