What Pokémon have Steam Engine?

Rolycoly, Carkol, and Coalossal can have Steam Engine — the full list is above.

When was Steam Engine introduced?

Steam Engine was introduced in Generation VIII.

Generation VIII Ability

Boosts the Speed stat drastically when the Pokémon is hit by a Fire- or Water-type move.

Raises the user's Speed by three stages when it is hit by a Fire- or Water-type attack. The attack still deals damage.

“Boosts the Speed stat drastically when the Pokémon is hit by a Fire- or Water-type move.”

Introduced: Generation VIII
Pokémon: 3
In short: Boosts the Speed stat drastically when the Pokémon is hit by a Fire- or Water-type move.

3 Pokémon can have Steam Engine.

What does Steam Engine do?: Raises the user's Speed by three stages when it is hit by a Fire- or Water-type attack. The attack still deals damage.
How many Pokémon have Steam Engine?: 3 Pokémon can have Steam Engine.
What Pokémon have Steam Engine?: Rolycoly, Carkol, and Coalossal can have Steam Engine — the full list is above.
When was Steam Engine introduced?: Steam Engine was introduced in Generation VIII.