So after nearly losing a raid to someone bringing a Rayquaza, and actually losing my only Chien-Pao raid to someone bringing a Lucario that got OHKOed every turn it was out, I decided despite this raid actually not being particularly difficult, I wanted to go a bit extreme in my attempts to idiot proof it. I turned to an old friend of mine for this...
FLING!
Anyone whose played a lot of Battle Stadium Singles before can tell you to never underestimate Fling + Light Ball, so I turned to a similar inspiration with Fling + Flame Orb! For Chien-Pao raids, time is money: as soon as stuff starts Terastallizing, Chien-Pao tends to go down quick, so I prefer Fling over the slower use of Reflect, especially since Fling pairs pretty well with a quicker more offensive support that I think works better against Chien-Pao! I'm gonna give a quick run down of the stuff I used!
Unless otherwise stated, all the EV spreads on these sets first focus on outspeeding the level 75 Chien-Pao, then maximizing damage, then maximizing bulk.
ALSO MAKE SURE YOU DON'T USE FLING UNTIL AFTER CHIEN-PAO's SHIELDS ARE UP!
Infernape @ Flame Orb
Ability: Iron Fist
Tera Type: Fighting
EVs: 24 HP / 248 Atk / 236 Def
Adamant / Naughty Nature
- Drain Punch
- Fling
- Close Combat
Infernape @ Flame Orb
Ability: Iron Fist
Tera Type: Fire
EVs: 24 HP / 248 Atk / 236 Def
Adamant / Naughty Nature
- Drain Punch
- Fling
- Raging Fury
- Fire Punch
Of the Fire / Fighting starters, Infernape hilariously ends up being the "bulkiest" since it needs no Speed investment! Thanks to Iron Fist, Drain Punch actually matches Urshifu's in damage output too! Now in normal circumstances, Urshifu-R is just straight up better thanks to its bulk... but with Infernape being part Fire, that means you can use Fling on turn 2 instead of waiting for Chien-Pao's early shield to go up, which is handy for match momentum.
Infernape comes in two flavors. The Tera Fighting focused on is the most versatile, being in my opinion the best suited towards team compositions that don't use sun whatsoever. However, if you come across someone using Koraidon or Groudon or something that's likely to use Sunny Day, the Tera Fire one is a really good option too! Note for the sets, Close Combat is the finisher you use AFTER Chien-Pao's shield is broken, same for Raging Fury.
Regardless of which Infernape you choose, thanks to Fling making Chien-Pao a wimp during its shield time and Drain Punch, Chien-Pao doesn't even get CLOSE to taking Infernape down. Hell, Ruination doesn't even matter too much thanks to Drain Punch on turn 1! Overall, I think Infernape is probably the Flame Orb flinger that fits the most situations. It being breedable means it's not gonna be too tricky to get either!

Groudon @ Flame Orb
Ability: Drought
Tera Type: Fire
EVs: 20 HP / 252 Atk / 176 Def / 60 Spe
Adamant / Naughty Nature
- Heat Crash
- Fling
- Sunny Day
For some freaky reason, Koraidon doesn't actually learn Fling (though funnily enough defensive Koraidon does sorta work in this raid anyways thanks to Drain Punch lol), so Groudon is the next best thing. Now I know what you're thinking, "OMG ITS ICE WEAK THO". Thankfully, since Groudon isn't moving an INCH before Chien-Pao's shields go up (you don't want Groudon getting burned after all!), this means after a burn, not even a critical Icicle Crash is 2HKOing Groudon thanks to that insane Defense stat!
Now on its own, I think the Ice weakness would make Groudon worse than Infernape and Volcanion... but the secret sauce lies in your teammates! Drought rules when so many people are bringing Fire-types. This combined with Groudon being so full of fat that Heat Crash actually gets the full 120 BP on Chien-Pao, and you got a shockingly strong offensive support Pokemon! So if you see the Fire-types coming out in your rando raids, this Groudon might be your best pick!
Just note due to the Ice weakness, if Groudon is the Ruination target, your best bet is to do a heal cheer after Flinging the Flame Ball against Chien-Pao's shield, since Ruination actually lets Chien-Pao 2HKO if it gets a critical hit Icicle Crash on you. This is actually why I think Infernape is the better pick if you see no Fire-type teammates, even if Groudon is dealing more damage.
Also: Sunny Day is literally only there in case someone tries to grief with Rain Dance or something lol. Never had to use it though!

Volcanion @ Flame Orb
Ability: Water Absorb
Tera Type: Fire
EVs: 24 HP / 12 Def / 252 SpA / 220 Spe
Modest / Rash Nature
- Weather Ball
- Flamethrower
- Fling
So first off: this thing has a 4x Ice resistance! That's nice as long as you don't get hit by a bazillion Crunch defense drops!
Now on its own, I find Volcanion riskier than Infernape. Sure, Flamethrower / Weather Ball deal quite a bit more damage than anything Infernape does, but the lack of Drain Punch means Ruination followed by a Crunch defense drop can be a bummer that forces a heal. However, the power difference is REALLY noticable if a teammate brings a sun setter with them (hence the Weather Ball!). So if you got the sun going up in your match, I think the risk of needing to waste a turn healing with a cheer is worth the sheer damage output Volcanion offers. It helps too that despite little investment, Volcanion's big defense stat means it doesn't really feel frail!
Reshiram @ Flame Orb
Ability: Turboblaze
Tera Type: Fire
EVs: 196 Def / 252 SpA / 60 Spe
Modest / Rash Nature
- Fusion Flare
- Fling
If you thought Volcanion did a ton of damage, Reshiram takes that even further, plus it has even more bulk! So why don't I have Reshiram up there with Volcanion? It's because of the neutrality to Icicle Crash. Reshiram is bulky enough to get away with it, ESPECIALLY after burning Chien-Pao through its shield, but Crunch defense drops with Icicle Crash critical hits still hurt, so its more vulnerable to hax overall than Volcanion is. Still, Reshiram is a lot easier to get since it isn't a mythical, so I think it's still a reasonable alternative!

Urshifu-Rapid-Strike @ Flame Orb
Ability: Unseen Fist
Tera Type: Fighting
EVs: 252 Atk / 252 Def / 4 Spe
Adamant Nature
- Drain Punch
- Fling
- Close Combat

Annihilape @ Flame Orb
Ability: Defiant
Tera Type: Fighting
EVs: 252 Atk / 196 Def / 60 Spe
Adamant Nature
- Drain Punch
- Fling
- Close Combat

Lucario @ Flame Orb
Ability: Justified
Tera Type: Fighting
EVs: 252 Atk / 196 Def / 60 Spe
Adamant Nature
- Drain Punch
- Fling
- Close Combat
These three all work in a super similar way: they're like Infernape except they can't attack until Chien-Pao's shields are up due to not being immune to burns, so they MUST use Fling before any other Attack.
This makes them worse than Infernape, and they don't provide Groudon's easy sun support... but they're still pretty damn good! Urshifu felt like the best to me, its way bulkier than Infernape, and once you fling that Flame Orb, it's basically bulkier Infernape that takes longer to get started! Annihilape doesn't have the resists to Chien-Pao's STABs, but Defiant turns Crunch hax into potentially crunchy wins! Finally, Lucario's Sacred Sword weakness isn't great, but since Chien-Pao won't hit you with it until its burned under its shield, Lucario can usually tank it thanks to Drain Punch. Justified is neat too, though since you can't attack until the shield is up, the Attack boost from Ruination will usually get Hazed away before you can even Fling.
Something nice to note too: Annihilape and Lucario are obtainable without the need for Pokemon Home or DLC, so they're pretty accessible!
The Failure

Heracross @ Flame Orb
Ability: Guts
Tera Type: Fighting
EVs: 176 HP / 232 Def / 100 Spe
Impish Nature
- Low Kick
- Fling
- Close Combat
So Heracross is the only Flinger that has Guts and also outspeeds level 75 Chien-Pao. Sounds great right? Well what did this in was Heracross not learning Drain Punch, which meant Ruination was a BIG problem. I also had to maximize its defenses since crits and defense drops after Ruination were even worse news! I do have to admit though, it DID hit hard thanks to Guts. Still, the awkwardness of its defenses and reaction to crits meant Heracross didn't really feel worth it.
Overall, I.. got sorta carried away with both this post and messing around with what's a pretty simple raid lol. Still, ever since I've been using this strat, I've been able to win even when little timmy forgets that Mega Dragonite isn't in the game!