iirc, (unboosted) adamant dragon rush can 3hko defensive lando-t and 2hko quagsire, mew, Toxapex, pyu, gliscor and a ton of other things that dragon claw misses out on. For this particular niche, it could be a viable middle-ground and potentially let you forego tpunch for another move (like roost or eq) if you don't care about Fini.SD + 3 Attacks Zard X
Charizard-Mega-X @ Charizardite X
Ability: Tough Claws
EVs: 32 HP / 252 Atk / 4 SpD / 220 Spe
- Swords Dance
- Fire Punch
- Thunder Punch
This set is a wallbreaker, obviously, and runs Dragon + Fire + Electric coverage, a combination with no resistances*. Max Attack and Adamant for extra meaty hits, enough speed for neutral-natured base 95's such as Zygarde and whatever runs 290 to creep them, with the rest for an odd-numbered HP value.
Outrage hits insanely hard even without a boost. If stuff like Quag isn't an issue and being locked into a move isn't preferred then Dragon Claw can be used instead. Fire Punch is used over Flare Blitz because it gets the same KOs after a boost while avoiding recoil, and Thunder Punch nails Water-types such as Toxapex and Tapu Fini. +2 Thunder Punch also 2HKOs even the bulkiest Heatran sets.
*Mega Altaria resists this combo but it's an unmon so whatever