Updated:

1. Charged creeper

/summon creeper ~ ~ ~5 {powered:1b}

No lightning needed. On Bedrock use the spawn event:

/summon creeper ~ ~ ~5 ~ ~ minecraft:become_charged

2. Explosion size (Java)

/summon creeper ~ ~ ~5 {ExplosionRadius:6b}

The default is 3. Use 0 for a harmless blast with only sound and smoke.

3. Fuse time (Java)

/summon creeper ~ ~ ~5 {Fuse:80s}

20 ticks is one second; the default is 30 (1.5 seconds).

4. Explode right away (Java)

/summon creeper ~ ~ ~5 {ignited:1b,Fuse:0s}

The creeper blows up as soon as it appears. Combine it with ExplosionRadius for a custom-sized blast at an exact spot, which is handy for traps and demolition in adventure maps.

5. Protect terrain

/gamerule mob_griefing false

Use mobGriefing on 1.21.10 and earlier and mobgriefing on Bedrock. See mob griefing.

6. Keep creepers away

/summon cat ~ ~ ~ {PersistenceRequired:1b}

Creepers run from cats and ocelots. See the tame pet command to make the cat yours.

7. A creeper that leaves a potion cloud (Java)

/summon creeper ~ ~ ~5 {active_effects:[{id:"minecraft:slowness",duration:200,amplifier:1}]}

A creeper with a status effect leaves a lingering cloud of that effect when it explodes. Swap slowness for poison or levitation for traps. See the effect ID list.

8. A creeper statue (Java)

/summon creeper ~ ~ ~5 {NoAI:1b,Silent:1b,PersistenceRequired:1b}

NoAI stops it moving and exploding, Silent mutes it and PersistenceRequired stops it despawning. Good for displays.

Troubleshooting

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