How does confusion damage work?

Question

Sometimes it does lot of damage,sometimes it does less damage.

Answer 1

Confusion

The confused condition causes a Pokémon to hurt itself in its confusion 50% of the time. The damage is done as if the Pokémon attacked itself with a 40-power typeless physical attack.

Confusion wears off after 1-4 turns. Pokemon with Own Tempo are immune to being confused.

Source

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