Ah yes, finally able to show off Dual's updated design; Differently shaped crystals, mainly. Just better placement and shape for the custom ones, like his hands and mask.

Not much has changed mechanically, he still can use two type memories at once, still has the Beast Memories to induce form changes based on the Ultra Beasts, and still has the Ultra Silvallium Z to allow him to mega evolve and use Omnifang.

I may as well write out more detail on Omnifang and his other special/signature moves, while I have the chance.

Like normal Silvally, he has a move in his standard set of 4 that changes type based on his; but this is known as Multi-Attack II, and it has the special property of behaving as if it is double-typed; the effectiveness of whatever 2 types Dual has engaged (If he even has 2 active) will be applied against the type(s) of the opponent together. For example, if he uses Fire and Grass, on a Water-type opponent, then it effectively behaves as though Dual used regular Multi-Attack with grass and fire against it but at the same time, in one turn.

Omnifang, then, is the Silvallium Z's unique Z move; instead of changing type based on Dual's type, it applies neutral move effectiveness no matter what type(s) the defending Pokemon is. It'll never be super effective, but it will likewise never be not very effective or completely resisted. The only thing that can change that is moves like Protect and Detect.

When Gigantamaxed, Multi-Attack II becomes G-Max Omniburst, an explosion of energy that, again, deals neutral effectiveness no matter what type is defending against it. This one comes with the added benefit of only being affected by Max Guard instead of Protect/Detect, as well.

When Gigantamaxed, Omnifang becomes Z-Max Omniblast, a sustained beam of energy that deals neutral effectiveness like the others. It also clears all stat changes on the enemy team, and nullifies status effects on the allied team. The user must recharge after using this attack, unless...

When Dual is Mega Evolved and Gigantamaxed simultaneously (Gigantamega'd, for short), Z-Max Omniblast becomes GZ-Max Soul Judgement, which deals neutral effectiveness against all defending Pokemon, cannot be blocked, clears all stat changes from the enemy team, and clears all status ailments from the allied team. It has a small chance to OHKO any Pokemon hit by it, which includes any allied Pokemon.

Now you're probably thinking "well geez Halyo that all seems pretty OP," and you're right. But remember, those last couple moves are locked behind Dual having a proper bond with a suitable trainer. He can't just snap his fingers and "boom you're dead" whenever he wants. Unless he really feels like he's in danger, Dual is pretty content with Multi-Attack II for his needs.

Also the original line work is by  SuperSonic1992 by the way.