rayquaza doesn't 100% outclass Kyurem though, Kyurem is bulkier 125/90/90 compared to rayquaza's 105/90/90 and has Ice STAB. rayquaza has X4 weakness against Ice
Bulk is moot as Kyu is not cut out to be a defensive pokemon; it was never meant for that role. Not to mention it still shares a stealth rock weakness with Rayquaza, but the latter isn't grounded and therefore doesn't fear spikes or toxic spikes, which Kyu is vulnerable to. Both are rock-weak but Rayquaza can also eat up Focus Blasts, Aura Spheres, Earthquakes, and Earth Powers, all of which are going to crawl up Kyu's ass and die. Kyu also is raped by priority, being vulnerable to all of them and taking heavy damage from Bullet Punch, Vacuum Wave, and Mach Punch.
And if you wanna talk stats, every dragon worthy of uber status discounting ex-OUs (salamence, garchomp) have Base 150 in one attacking stat or both, not to mention soul dew Lati@s. Bottom line its completely outclassed by just about every dragon in the tier as far as raw attacking power goes with Dragon STAB. Its Draco Meteors and Outrages are going to fail to score the OHKOs that its fellow dragons are capable of. Kyu also gets ZERO boosting moves (claw sharpen does NOT count, name one uber you'd use that move with), which just knocks it down another notch below the likes of Rayquaza, Latios, Palkia, etc.
Also, Rayquaza has Extremespeed and an offensive movepool that puts Kyu to shame. As does every dragon-typed uber from the first 4 generations. Reshiram and Zekrom may have equally lacking movepools but thanks to their abilities they have absolutely zero need for coverage moves. The only decent coverage moves Kyu gets are Stone Edge (physical) and Shadow Ball (special), which furthers the need to split offensive EVs, further weakening the overall power of its attacks in relation to its dragon-typed brethren. Even Reshiram/Zekrom get more coverage moves than that, having the former two in addition to Solarbeam/Focus Blast and Shadow Claw/Payback respectively. Even if Reshiram and Zekrom were out of the picture, I challenge anyone to find something this guy can do that Dialga and Palkia can't manage either.
If you focus more on its Ice STAB, thats all well and good, as it gives you the most powerful (and only STABed) Ice Beam in the tier, assuming it winds up uber (this is all assuming it winds up uber). But its signature moves are crap, and Frozen World is going to cause switches, but little else. Aside from that, there isn't anything it can do that its other dragons can't do better IMO, aside from spamming Blizzard on hail teams (which are a joke in the higher tiers, lets face it).
If you ask me what Kyuremu needs is for someone to switch its HP with its Speed, then you'd have a unique and niche-worthy uber dragon on your hands, if not a top tier uber.
 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		
 
 
		 
 
		 
 
		 
 
		



 
	 
 
		 
 
		 
 
		 
 
		