Fire

Moltres is a large, avian Pokémon with a light yellow plumage. It has a long, flowing head crest and a billowing tail, both made of reddish flames. Additionally, its wings are also shrouded in fiery plumage. It has a long, thin neck, a pointed, brown beak, and small, triangular eyes. Its thin, brown legs have anisodactyl feet, with three forward-facing digits and one facing backward.

Moltres sheds embers with every flap of its wings, creating a brilliant flash of flames: This display is said to have inspired the legend of the phoenix in An Illustrated Book of POCKET MONSTERS. In The Power of One (M02), its fire is said to have combined with 's ice to create the ocean's cradle, and it has some connection to the weather of the Orange Islands. By dipping itself into the magma of an active volcano, this Pokémon can heal itself. Rarely seen, It migrates from the south with the coming of spring, and is said to bring an early springtime to cold lands. There have been stories of Moltres using its wings to assist those lost in the mountains. As seen in Pokémon Horizons, like other Legendary Pokémon, Moltres can be found in the Pokémon paradise Laqua. Moltres loves Moltres Treats made by Snacksworth, who once encountered it in the past.

Forms
Moltres has a regional form: Galarian Moltres.

In Galar, Moltres has a similar build, but a drastically different color scheme. Its body is primarily black with scarlet highlights and bright blue eyes. Its scarlet beak is hooked at the tip and leads to markings that run down its front and behind its head. Its feet are also scarlet with black talons. Its wings, crest, and tail are mostly black, with the crest having an extra curl at the front and the tail being split in two, and all three of these features exude a magenta, flame-like energy that earns it the name of its Kantonian counterpart. Its body apparently feels lukewarm to the touch.

The sinister energy that blazes from within its body is so oppressive that most Pokémon can't even approach it. Galarian Moltres attacks by spreading its wings wide to unleash its energy in a powerful aura that attacks the minds of its foes, inflicting deep fatigue as it burns away their energy from within. The aura has the power to consume the spirit of its victims, reducing them to burned-out shadows of themselves. As seen in Charge! Galar Mine! (HZ022), the only way to overcome the effects of its aura is to have a strong spirit. It is said to have a haughty personality and a calm demeanor. It is constantly migrating around the world but can be found in the Crown Tundra once every few decades congregating with the other birds at the Dyna Tree to eat its fruits.

(Source: Bulbapedia)