The official Movie 19 Website has opened. Translations follow:

Volcanion enters with a heatburst!

Volcanion

It uses fire and water to create steam heatbursts within its body, expelling explosive shock waves and boiling steam from the arms on its back.
The power is said to be great enough to blow away entire mountains and forests, gouging out the earth and changing the shape of the land.

Species: Steam Pokémon
Type: Fire/Water
Height: 1.7m
Weight: 195.0kg
Ability: Water Absorb

Posters

Trailer

The world premiere of the "teaser" will be shown on Oha Suta Thursday December 17th!
Airs on the TV Tokyo Network at 6:45am

Source: http://www.pokemon-movie.jp/