I'm not actually using Garchomp, so I just wanted to say something I'm finding is doing well against it.
Landorus-T: I've been finding that time and time again when I'm on the verge of being finished off by SD Chomp that it is just a great check. Earthquake does solid damage, and after Intimidate it is fit to take even an Outrage. ScarfChomp it just completely destroys, taking little from all of its attacks and hitting back hard with Earthquake. It is immune to Garchomp's own Earthquake, which is very useful. When you look at solid calcs:
252 Atk Garchomp vs. 252/196 Landorus-T (assuming Intimidate, Leftovers, and Stealth Rock)
- -1 Outrage: 117-138 (30.62 - 36.12%) -- 75.15% chance to 3HKO after Stealth Rock
- -1 Dragon Claw: 78-93 (20.41 - 24.34%) -- possible 5HKO after Stealth Rock
- +1 Outrage: 262-309 (68.58 - 80.89%) -- guaranteed 2HKO after Stealth Rock
- +1 Dragon Claw: 175-207 (45.81 - 54.18%) -- 98.44% chance to 2HKO after Stealth Rock
- neutral (CB) Outrage: 175-207 (45.81 - 54.18%) -- 98.44% chance to 2HKO after Stealth Rock
- neutral (CB) Dragon Claw: 118-139 (30.89 - 36.38%) -- 83.76% chance to 3HKO after Stealth Rock
96 Atk Landorus-T against 4/0 Garchomp (no Stealth Rock: Earthquake: 184-217 (51.39 - 60.61%) -- guaranteed 2HKO
against Scarf: It can switch into any hit, not even being always 3HKOed by Outrage. Earthquake always 2HKOes, so Landorus-T can easily switch-in, and if gets hit by Outrage, you can even switch to a Steel-type if you want to to more comfortably handle Outrage.
against Band: If it needs to, it can come in after something has died and take an Outrage. You can also have something bait Earthquake and get in Landorus-T for free.
against Swords Dance: It can't come in after +2, but before it, it can switch in, get Garchomp at -1/+1 if it Swords Dances that turn. It can get off a solid chunk of damage with Earthquake while surviving an Outrage after Stealth Rock damage. Earthquake is a solid 2HKO on non-SubSD, and it has a 91.8% chance of 2HKOing SubSD, which is much weaker.
While it may not be a counter, Landorus-T is a solid check to Garchomp and should be considered if your team has trouble against Garchomp and other physical attackers that don't get a super effective hit on it.
Some observations on the Suspect meta as a whole:
- I'm seeing Hippowdon all over the place. I imagine it's great to check Garchomp, and its high physical bulk seems greatly needed atm.
- Sand is totally dominant. Perhaps the main reason for this is that Garchomp doesn't like weather-boosted attacks? I don't completely understand why sand is so common, but that might be a contributing factor. Or maybe people just have the mentality that Garchomp is always best in sand from back when it was legal in BW1?
And one more thing: Amoonguss with Def investment (I was running like 252/228+ or something, with 28 SpA EVs for Keldeo's Substitutes or whatever) can be a last-ditch check if in top shape, barely surviving a +2 Outrage and being able to Spore or KO it if it's weakened with HP Ice.
EDIT: also imho Garchomp is not broken or even close to being