Efficiency

Efficiency is an enchantment that increases the player's mining speed.

Obtaining
Efficiency V is available only when using an anvil for diamond and stone tools. Wooden, golden, iron and netherite tools can get Efficiency V by enchanting.

^Those two sentences contradict each other.

Usage
The proper tool for a block must be used in order to receive the speed benefit; the enchantment has no effect if the block is mined with the incorrect tool. See for details on mining speed.

The speed increase applies to all blocks that drop an item when mined.

Efficiency applied to an axe increases the chance that the axe may stun a shield, with the base chance being 25% and a 5% increase for each level of efficiency.

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