This could mean nothing but Mega Dragonite having a special moveset here + using Draco Meteor and Air Slash in the Champions trailer could point to it being a special attacker which would be very fun and a good way to differentiate from its base form and Mega Salamence while taking advantage of Gen 1 Movepool Magic
Hm, the difference between Dragonite's Atk & SpA is 34. Now I suppose they could always slightly decrease Atk, though that does feel like it's going too much against base Dragonite. I guess they could do a Mega Lucario and make its Special slightly higher than Atk making it a psuedo mix attacker (though then again the reason they did that for Lucario is because people were already playing it as a physical attacker).
91/134/95/100/100/80//600 > 91/134/115/140/120/100//700?
I guess its different enough from Mega Salamence (though with M-Salamence being faster it would probably still be considered better), and of course that's not taking into account Ability which likely won't be Aerilate. At this point I think we should just wait to see what's GF is cooking because they're obviously trying to not be predictable.
I always assumed each Pokemon would only be able to use a single gimmick at once… anything else feels completely off and OP
Which is my point. Because mechanically speaking these things seem possible:
* Mega Pokemon can Dmax or Terastallize. Neither require a form change, one makes your Pokemon bigger w/ 3 swirly clouds and another adds a crystal overcoat w/ a symbol crown.
* A Pokemon holding a Z-Crystal can D/Gmax or Terastallize, whether or not they used it already. While they likely can't use the Z-Move while D/Gmax, nothing seems to suggest they couldn't do as Terastallized-backed Z-Move.
* A D/Gmax Pokemon either Mega Evolving, using a Z-Move, or Terastallizing after they shrink back down.
There would need to be additional limitations programmed so each Pokemon is only allowed one Super Gimmick. Question is how "limiting/free" will this be? Cause only a Pokemon holding a Mega Stone and Z-Crystal can use their gimmick, but any Pokemon can Dmax or Terastallize (even if they forbid a Pokemon holding a Mega Stone/Z-Crystal to have access to them as options that's 4 other Pokemon who can be given a sudden bused on the whims of the battle). Unless, that is, for balance they force you to select a specific Pokemon that can only D/Gmax and can only Terastallize. While the latter option somewhat goes against one of the advantages of those Super Mechanics, in a game which has all the Super Mechanics it may be a required balancing trade off.
Ampharos whiffs a Thunder on Gyarados in this background segment after the first kill, with multiple angles to help. It seems to charge up on a specific area where the mon was, but takes plenty of startup time so despite being point blank to start, Gyarados just swims away.

: *
Watches the large lightning bolt strikes just in front of it* ... Nope. No. Niet. Nien. Me and my double weak fins are out of here!
If the white section was divided into four even parts, we'd expect that the pointer would be in-between two symbols when it's splitting that section down the middle. Instead, it's at the middle of the Z-move icon, implying an odd number of possible selections. There is also the possibility that the Dynamax icon is just extremely wide, but it is usually shown as something that fits neatly within a square.
Or it's just currently selected on Z-Move in the image. I imagine you're able to rotate the white part with the symbols on it so the arrow is pointing to the Super Gimmick you want to use.