>>58496217It genuinely depends on the Mega's ability.
If it's still adaptability, it'll be a better attacker/bulkier physically but less specially resilient than AV Dragalge or a weaker but much bulkier variant to Specs Dragalge.
If it gets Regenerator, it'll still hit hard (132 attack), but it'll be an absolute pain in the ass. It has toxic spikes, flip turn, Draco-meteor, dragon tail, on a 65/105/163 bulk with 132 Special attack. As the pokédex implies, it'll be cancer to fight it on the special side.