Z-Crystal Name: Ninetalium-Z
Z-Move Type: Grass
Z-Move Power: 210
Required Move: Solar Beam
Category: Special
Z-Move Name: Nature's Blessing
Z-Move Description: Ninetales' tails glow green and surrounds itself in a green aura, suddenly the battlefield is surrounded in harsh sunlight, and then Ninetails fires a beam from its whole body at the foe... causing an explosion.
Z-Move Effect: Changes Ninetails into a Grass-type, gains +1 Special Attack, and activates Harsh Sunlight (Desolate Land) before it launches its attack, always causing burn on the foe.
Explanation: (Remember Ninetails only has base 81 Special Attack, so +1 Special Attack helps make up for it's low base stat, and it's lack of Life Orb. Also it's lack of a decent Defense and it's Fire typing justifies a Burn status). By turning into Grass-type, it loses its Ground-type, and Water-type weaknesses, while being neutral to Ice, Bug, and Fire Attacks. Overall, Fire/Grass is a very balanced dual typing.