Updated:

1. Give the strongest mace (1.21.5+)

/give @p mace[enchantments={density:5,breach:4,wind_burst:3,unbreaking:3,mending:1,fire_aspect:2,looting:3},unbreakable={}]

Density and breach cannot be combined in survival, but a command adds both. On 1.20.5 to 1.21.4 write enchantments={levels:{density:5,breach:4}}.

2. Mace enchantments

IDMaxEffect
densityVMore damage per block fallen
breachIVReduces the target armor
wind_burstIIILaunches you up after a smash

More IDs: enchantment ID list.

3. How smash attacks work

Hitting while falling more than 1.5 blocks is a smash attack. Damage grows with fall height and you take no fall damage on a hit. Wind burst bounces you back up for another smash.

4. Add wind charges

/give @p wind_charge 64

Throw one at your feet to jump high, so you can smash on flat ground.

5. Practice target

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

See the NoAI command.

6. Density or breach?

Survival lets you choose only one. Density suits high drops with wind charges or wind burst. Breach suits fights against netherite players and armored mobs. Commands let you test both first.

Troubleshooting

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