Your current team isn't a Hyper Offense team. Hyper offense generally has a hazard setting suicide lead, a few set up mons, and dual screens. There's no room for defense on HO.
Blaziken
Hone Claws High Jump Kick is vastly inferior to Swords Dance Close Combat. Life Orb is also much better than Rocky Helmet (I don't know why you're using Rocky Helmet in the first place). If you're using a mixed attacker, something like a Hasty / Naive nature would be better, but mixed Blaziken is bad.
Blaziken @ Life Orb
Ability: Speed Boost
EVs: 252 Atk / 4 Def / 252 Spe
Jolly Nature
- Close Combat
- Swords Dance
- Flare Blitz
- Earthquake / Knock Off
Glastrier
You should be running 252 HP / 252 Atk / 4 Def instead of 4 HP / 252 Atk / 252 Def. Glastrier as a whole is pretty bad. The best Ice type in the metagame is Weavile.
Weavile @ Choice Band
Ability: Pickpocket
EVs: 252 Atk / 4 Def / 252 Spe
Jolly Nature
- Triple Axel
- Knock Off
- Ice Shard
- Low Kick
Kartana
That set is laughably terrible. Assault Vest Kartana is really, really terrible in singles, since the lack of Dynamax and the metagame's more offensive pace combined with its lack of very useful resistances outside of Moonblast and Volt Switch makes it impossible for Assault Vest Kart to be viable. Last Resort doesn't OHKO Dragonite from full health, actually. It 3HKOes with Mutiscale and no Attack boosts. 2 powerful Physical attackers are likely enough, and your team so far doesn't look to have a very good matchup against Toxapex and Heatran, so Slowking would work very nicely here.
Slowking @ Heavy-Duty Boots
Ability: Regenerator
EVs: 252 HP / 4 Def / 252 SpD
Calm Nature
- Scald
- Future Sight
- Slack Off
- Teleport
Mudsdale
Mudsdale has high HP, high attack, high defense, decent special defense, and poor speed. Landorus-Therian has high HP, higher attack, Intimidate to make it more immediately bulky, better special defense, and good speed, along with excellent role compression, versatility, and great moves like Knock Off and U-turn. Is there any reason to use Mudsdale over Landorus-Therian? No. In my opinion, Weavile's high Speed and Ice Shard is good enough as speed control, but you can run Choice Scarf. This team doesn't have a good Stealth Rocker at the moment, and Landorus-Therian, with its myriad of great traits, is arguably the best one in OU.
Landorus-Therian @ Leftovers / Rocky Helmet
Ability: Intimidate
EVs: 252 HP / 112 Def / 144 Spe
Impish Nature
- Earthquake
- Stealth Rock
- U-turn
- Toxic / Knock Off
Tornadus-Therian
Hurricane misses are not enough justification to run Blunder Policy. Never run 252 Atk / 252 SpA and a Serious nature on a mixed attacker. Tornadus-T is better as a Defogger with Heavy-Duty Boots to take advantage of Regenerator and to get rid of its Stealth Rock weakness. Defog Tornadus-T is doing worse right now, since Corviknight has reliable recovery in Roost, and isn't threatened as much by Pokemon like Weavile, who can KO Tornadus and keep hazards on the field.
Corviknight @ Leftovers
Ability: Pressure
EVs: 252 HP / 252 Def / 4 SpD
Impish / Relaxed Nature
- Brave Bird
- Roost
- Defog
- U-turn
Hydreigon
Rocky Helmet is bad on an offensive Pokemon. What does Dual Wingbeat cover? Hydreigon is much better off using a Nasty Plot + Roost set. You already have a Dark type though. Dragapult is probably the better choice, since Ghost is an incredible type right now and Dragapult can abuse it well. You have two options here; go with Choice Specs to wallbreak and even clean late-game with Shadow Ball and its checks being worn down, or go with the Hex pivot set to spread status throughout a game and clean up with powerful Hexes.
Dragapult @ Choice Specs
Ability: Infiltrator
EVs: 4 Def / 252 SpA / 252 Spe
Timid Nature
- Draco Meteor
- Shadow Ball
- U-turn
- Flamethrower / Thunderbolt
Dragapult @ Leftovers / Heavy-Duty Boots
Ability: Infiltrator
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
- Hex
- Draco Meteor
- U-turn
- Will-O-Wisp / Thunder Wave
So, there it is. I built a balance team, but if you want a hyper offense team, here it is.
Cores
+
Landorus-T softens physical blows with Intimidate and has a U-turn resistance and Volt Switch immunity, while Slowking switches into Hydro Pumps and Ice Beams for days with its incredible Special Defense and Regenerator.
+
Corviknight's Defog support is something Choice Band Weavile really appreciates. Its good physical bulk lets it switch into moves that Weavile can't take. In return, with correct U-turn timing, Weavile can scare out some Pokemon that Corviknight cannot handle.
+
Slowking's Future Sight support makes Dragapult's attacks much stronger. This lets it break past Pokemon it usually can't get rid of in one hit.
Landorus-Therian provides U-turn and Toxic/Knock Off support, which is helpful for every single Pokemon on this team.
Bonus core: You can replace Blaziken with Kyurem and Weavile with Bisharp for this core to work. I like Kyurem + Bisharp + Hex Dragapult, because Kyurem removes Pokemon Bisharp has trouble against, like Physdef Hippowdon while Bisharp gets rid of Blissey and Tyranitar. Bisharp and Kyurem are both very good wallbreakers by themselves, so Hex Dragapult can clean up the enemy's remains in the late game.
