AZUMARILL: Banded set has a pretty solid chance of ohko-ing the bug with return-boosted move and almost always lives an unboosted hit, cannot switch into one, though
252+ Atk Aerilate Mega Pinsir Return vs. 252 HP / 0 Def Azumarill: 327-385 (80.9 - 95.2%) -- 56.3% chance to OHKO after Stealth Rock
CHARIZARD-X: Similar circumstances as Azumarill, but is guaranteed to OHKO with Flame Charge or any other Fire move
252+ Atk Aerilate Mega Pinsir Return vs. 0 HP / 4 Def Mega Charizard X: 247-292 (83.1 - 98.3%) -- guaranteed OHKO after Stealth Rock both of these mons cant have prior damage to retain a "Checking" status.
DIANCIE-MEGA: Debatable switchin, ultimately comes down to 50/50's between using either Protect or any Rock attack of your choice if switched in after a Swords Dance, otherwise Diancie wins 1v1, though it still fears Earthquake.
not a switchin...it gets 2hkoed by feint if already megaed, meaning even as a check, its a pretty shaky one, since after SD it safely OHKO's diancie.
+2 252+ Atk Aerilate Mega Pinsir Return vs. 0 HP / 0 Def Mega Diancie: 250-294 (103.7 - 121.9%) -- guaranteed OHKO
GARCHOMP: Though Garchomp does have the bulk to potentially stand up to two Returns, it isn't sustainable and is still forced to run a Rock move to do any real damage to Pinsir.
GLISCOR: Needs to be maximum physical bulk to avoid the 2HKO, and in addition, needs to have already been poisoned prior to switching in, in order to not get 2HKO'd, not to mention, needs either a Rock type move or to have disposed of its Toxic Orb in order to OHKO
ill give you these, they kind of work if it doesn't manage to setup.
HEATRAN?: Little purpose in Return'd other than just being a normal Heatran that also gets marginally improved attacks. Scarfed variant forces Pinsir out, which, if coupled with SR, is usually all you need.
fun fact:
+2 252+ Atk Aerilate Mega Pinsir Return vs. 28 HP / 0 Def Heatran: 258-304 (78.1 - 92.1%) -- 31.3% chance to OHKO after Stealth Rock of course, SDing isnt really easy, but considering this is a wallbreaker, its a pretty serious issue to be able to OHKO resists.
HIPPOWDON: Potential switchin to Pinsir, requires a Rock type move to counter, unfortunately, and even then, is basically wasted after taking a +2 Return.
KLEFKI: Not an adequate matchup for Klefki, but is at least able to set up screens to support an alternative check/counter, as well as hinder opponents with Thunder Wave, though it usually has little effect on Pinsir, due to Feint being +2 priority.
ill give these too.
KYUREM-BLACK: Bulky offense that cannot switch in, but will OHKO an unboosted Pinsir.
252+ Atk Aerilate Mega Pinsir Return vs. 0 HP / 0 Def Kyurem-B: 271-321 (69.3 - 82%) -- 56.3% chance to OHKO after Stealth Rock. see: azumaril
LANDORUS-THERIAN: Bulky offense that is capable of switching in and taking a hit, as well as OHKO-ing back, but, similar to other threats, is still generally left in an unsustainable position afterwards.
MAGNEZONE/TON: Generally scarfed threat that serves little purpose other than being able to withstand Flying damage due to its typing and gain momentum by using Volt Switch, though can be checked in return with the opposing Pinsir carrying Protect for move scouting and switching, since it has a free move slot from not needing to run Return/Frustration, and having both Earthquake and Close Combat is generally unnecessary.
ill give these too.
MANECTRIC-MEGA/RAIKOU/THUNDURUS//THERIAN: Serves little purpose other than revenging and attempting to regain momentum, since they lack the bulk to safely switch in, and are still left with an undesirable amount of HP afterwards, anyways.
all but mane fall to +2, but yeah, they check.
METAGROSS/MEGA: Like most alternatives, it can threaten Pinsir with Bullet Punch, but is unlikely to OHKO, and is left with little HP after knocking out Pinsir
first mon you mentioned that isnt ohkoed by +2 feint...that kind of tells you something doesn't it.
ROTOM: Has very little purpose other than being a designated check to Pinsir, but is ultimately threatened by the possibility of Mold Breaker Earthquake pre-mega, and ultimately has difficulty sustaining itself.
it also gets taken down to like...10% of health if at +2
SCIZOR/MEGA: Is almost always 2HKO'd, and isn't capable of doing very much back beyond Bullet Punch.
you basically argued this point for me lol.
SKARMORY: Easily switches in and sets up with Curse, which is enough to nullify Pinsir's Sword Dance, faces difficulties if lacking Leftovers, however. Utility Skarmory is generally dead weight.
"sets up with curse" ...do skarms actually do this? and yeah...it counters.
SLOWBRO/MEGA: While Either Slowbro has the capacity to set up themselves with Iron Defense, neither are capable of switching in, and still cannot stop Pinsir once it is set up to +2.
argued my point for me.
TYRANITAR: Destroyed by Close Combat, only manages to threaten Pinsir with a Choice scarf, which can be scouted out with Protect, and otherwise becomes a 50/50 between using Pursuit or any Rock attack of your choice.
+2 252+ Atk Aerilate Mega Pinsir Return vs. 0 HP / 4 Def Tyranitar: 249-294 (73 - 86.2%) -- guaranteed 2HKO after Stealth Rock not to mention it too, gets beaten up bad by feint and cannot have any prior damage before facing +2.
ZAPDOS: Almost always forces Pinsir to switch out, but can be threatened by a potential +2 Stone edge, which, while rare, is doable, since Pinsir has a spare move slot to do anything with.
AERODACTYL-MEGA: Despite having type advantage, it is still 2HKO'd and can only be used as a revenger, otherwise you need to sacrifice a lot of either Speed or Attack investment to survive an attack on switchin.
AGGRON-MEGA: Doesn't really have a significant purpose in Return'd other than acting as a soft check to Pinsir, which, in that regard, it still does poorly, since it is required to run either Avalanche or a Rock type attack to safely OHKO Pinsir, otherwise, it is left with little remaining HP.
CRAWDAUNT: Requires a lot of bulk to make it guaranteed to survive a Return, but will OHKO an unboosted Pinsir if Banded
who runs max hp craw. its WAY too frail and slow to wallbreak with hp
DOUBLADE: Unsustainable check with very little purpose other than attempting to threaten Pinsir, which it cannot do without a Rock type attack.
aka, pinsir sets up and sweeps.
MAMOSWINE: Requires either bulk evs or a sash to safely survive a Return and OHKO back.
MANDIBUZZ: Can safely switch into Pinsir and 2/OHKO with Foul Play, but like most defensive checks, is left very weak afterwards.
RHYPERIOR/REGIROCK/CARRACOSTA: Unlike most other defensive checks, these can switch in on an attack and be fine, though they are still difficult to sustain, and ultimately will be left in a relatively crippled state if Pinsir uses Swords Dance and then Close Combat.
AURORUS?: Requires a Choice Scarf to outspeed Pinsir, as well as a small portion of defense evs to safely withstand a +2 Adamant Return, but otherwise safely outspeeds and OHKO's otherwise, though will still be left in a hindered state if Pinsir uses Feint over Close Combat/Earthquake.
QUAGSIRE?: Cannot switch into an attack, but can switch into a predicted Swords Dance, or after a Pokemon has been knocked out. Proceeds to set up with Curse and attempt to sweep, as long as there are no special attackers around.
AVALUGG: Safely switches in on anything Pinsir does and OHKO's with Avalanche, but is generally still left in a crippled state afterwards.
DITTO: Can force a Pinsir to switch out, which, if SR is present, will hurt badly, while Ditto does not suffer as much from it.
SOLROCK: Is similar to the three prior Rock types, but also has the utility of burning and healing on its side.