Threats of the Round

Galarian Zapdos has enjoyed an uptick in usage in the recent weeks thanks to its ability to threaten double Steel cores made popular because of Hail and take advantage of Landorus-T's dominant presence in the OU tier, so it comes to no surprise that it's a premier threat to this week's core. Being immune to Spikes and able to take advantage of Defog, this jacked bird isn't phased at all about what Ferrothorn and Landorus-T do with their first slot. Immunity to Earthquake and resistance to Power Whip and Body Press give Galarian Zapdos chances to enter the field and threaten the opposing teams with its powerful STABs, although it hates losing its Choice Band to Knock Off. It does take a lot of damage between Brave Bird recoil and Iron Barbs, but the destruction it creates is well worth it.

Exchanging a fancy bandana for some boxing gloves, Urshifu-R becomes a massive threat to this core: usually, it has to carefully choose which STAB to click since Landorus-T can pivot into Close Combat and Ferrothorn into Surging Strikes, but this set trades Choice Band's power with Protective Pads' flexibility to switch moves and taking no passive damage from Ferrothorn's Iron Barbs which is especially relevant when clicking Surging Strikes. It has slightly more trouble switching into either than Galarian Zapdos has and really hates getting its item knocked off, but, if it manages to switch in safely, it becomes a massive threat to the core.

Definitely less viable than the previous two, Xatu takes a different approach when dealing with this core: it prevents any progress being made, be it hazards or Landorus-T's Toxic (which gets reflected back at it) and Ferrothorn's ever-annoying Leech Seed. The best they can do is removing its item with a super-effective Knock Off, but, without Attack investment and Xatu's access to reliable recovery, Xatu can easily stomach Knock Offs and keep blocking the core from working properly. Heat Wave puts the nail in the coffin for Ferrothorn as well, having a 50% chance to 2HKO.
Additional Notes

Another off-beat pick, Conkeldurr packs more than enough power to absolutely pummel the core with STAB Close Combat for Ferrothorn and Facade for Landorus-T. However, not only does it suffer from overall lack of viability outside Trick Room realistically (which means Landorus-T is faster than it), it gets worn down pretty quickly thanks to the constant burn damage from the required Flame Orb and it requires a lot of prediction to land the correct move against the correct Pokémon: Landorus-T's Intimidate and Ferrothorn's Iron Barbs are quite troublesome for Conkeldurr to predict against, which makes this pick much less reliable than the previous ones.

With a STAB combination that evicerates both Landorus-T and Ferrothorn and enormous power backing them, Volcanion stands out as a massive offensive threat to the core. However, running Choice Specs with a Modest nature leaves it exposed to many risks when handling the core in battle. First of all, Volcanion doesn't switch in at all, but it is also required to predict correctly because it will not have many chances to attack, due to being extremely vulnerable to both Stealth Rock and Spikes. Depending on Landorus-T's spreads, Modest Volcanion may also be slower than it, and while the chance of it happening has reduced since Landorus-T now prefers maximun investment, it is still there and needs to be accounted for. These flaws hinders Volcanion's reliability when handling this core.

Kartana once again makes it into this section, being an important threat to the core but with some glaring flaws. With base 181 Attack, Life Orb + Swords Dance and good attacking options in Knock Off and Sacred Sword and STAB Leaf Blade, it doesn't have any trouble in overpowering the core
on paper, but Life Orb recoil and, once again, the need to predict correctly in order to take as little chip damage as possible makes it less reliable, especially when taking into account its vulnerability to Spikes and necessity to be already boosted to threaten a KO on either. In a pinch it can get one easily, but then it becomes even more prone to killing itself against smart pivoting by the opponent.