Updated:

1. Summon the wither

/summon wither ~ ~ ~10

The wither appears ten blocks away and attacks at once. It has 300 health in Java and 600 in Bedrock. The command is the same in both editions.

2. Replay the build-up (Java)

/summon wither ~ ~ ~10 {Invul:220}

Like a built wither, it glows while its health fills, then explodes before it moves. Invul is that delay in ticks; 220 is about 11 seconds.

3. Stop block damage

/gamerule minecraft:mob_griefing false

Use mobGriefing in Java 1.21.10 and earlier, or mobgriefing on Bedrock. This also stops creeper damage; see mobGriefing.

4. Frozen statue (Java)

/summon wither ~ ~2 ~ {NoAI:1b,Invulnerable:1b,PersistenceRequired:1b,Silent:1b}

The boss bar still shows nearby.

5. Remove it

/kill @e[type=wither]
/kill @e[type=wither_skull]

6. Just the nether star

/give @s minecraft:nether_star

7. Prepare for the fight

/give @s minecraft:netherite_sword[enchantments={smite:5,unbreaking:3}] 1
/give @s minecraft:milk_bucket 3

Troubleshooting

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