I've found Red Orb Togekiss is a solid check to Absolite Manaphy - with a spread of 248 HP / 252 SpA / 8 SpD it can endure a +3 Hidden Power Ground and OHKO back with Solar Beam. I haven't faced a Sceptilite Manaphy yet, so I have no idea how it performs against that.
Assuming Red Orb Togekiss is carrying a Fairy STAB, it's a reliable check to both variants, and indeed the default trifecta of Scald/Energy Ball/Ice Beam is unable to 2HKO Specially Defensive Red Orb Togekiss even at +6.
I don't think Manaphy is banworthy. Good, yes, but not broken. It had two viable sets and you know it will run two moves (TG+Scald, Surf is generally inferior because of the burn chance) and it has 3 choices of coverage move (Ice Beam, HP ground, GK|Energy Ball). It's always walled by something and Blissey - without a grass move it's stopped by bulky waters and itself, without HP ground it's walled by certain Red Orb mons.
Blue Orb sets relying on sheer, overwhelming Scald/Surf firepower also show up, and among other points will power through Sablenite Blissey.
Absolite and Sceptilite are its main/best sets, not its only competitively valid sets.
-Sceptilite Energy Ball Manaphy can beat Absolite iirc
Absolite will outspeed, and without a Tail Glow Energy Ball isn't a OHKO. After a Tail Glow, Absolite Manaphy's Energy Ball/Ice Beam is a 2HKO. Shaky (Sceptilite loses if switching into Absolite Tail Glowing), and also kind of silly to say that Manaphy checks Manaphy.
-Red orb Tini can survive +3 HP Ground with 252/12 and has a 62.5% chance of OHKOing back with modest Solar Beam
Sceptilite has a less than 75% chance of being 2HKOed. Bulky Red Orb Victini strikes me as an odd choice, personally, and in any event is shaky since even with HP investment Stealth Rock will instantly turn that into a OHKO.
-CM Sablenite Blissey comes in on anything Manaphy does and only really dislikes the burn chance (but it still wins bar crits, even if it comes in on a TG). Slowbronite might also do ok.
Except the Blue Orb set.
+6 252 SpA Manaphy (Blue Orb) Scald vs. 0 HP / 252+ SpD Blissey (Sablenite) in Heavy Rain: 360-424 (55.2 - 65.1%) -- guaranteed 2HKO
-Cameruptite Hoopa doesn't even need to invest to tank any +3 attack (no, Manaphy isn't running signal beam or dazzling gleam) and OHKOs back with Timid Tbolt/Energy Ball
+3 252 SpA Manaphy (Blue Orb) Scald vs. 252 HP / 0 SpD Hoopa Unbound (Cameruptite) in Heavy Rain: 325-384 (89.2 - 105.4%) -- 37.5% chance to OHKO
Surf would be a OHKO, of course.
-Manectite Thundy can come in on any attack if it's already mega'd, and outspeeds and almost always OHKOs with Tbolt
Sceptilite wins.
-Sablenite Mew can come in on anything, and if it's running Anmesiapass (which I've seen surprisingly often) then it walls Manaphy to hell and back
+3 252 SpA Manaphy (Blue Orb) Scald vs. 252 HP / 252+ SpD Mew (Sablenite) in Heavy Rain: 264-312 (65.3 - 77.2%) -- guaranteed 2HKO
Shaky against Blue Orb.
-Univested Ekiller can come in on any attack and usually 2HKO
... if you mean Arceus, you're risking Scald Burns. If you mean the -atespeeds, they all either are risking a Scald Burn for switching directly in or are a Fire type and so risking being KOed on the way in.
+3 252 SpA Manaphy (Blue Orb) Ice Beam vs. 252 HP / 0 SpD Zygarde (Altarianite): 512-604 (121.9 - 143.8%) -- guaranteed OHKO
Why Blue Orb? Because it's the weakest Special Attack boost of the three, and it still OHKOs Altarianite Zygarde with Ice Beam if it has Tail Glow up.
-Red Orb Tran beats HP Ground-less Manaphy with ease
252+ SpA Heatran (Red Orb) Fire Blast vs. 0 HP / 0 SpD Manaphy (Sceptilite) in Harsh Sunshine: 94-111 (27.5 - 32.5%) -- guaranteed 4HKO
252 SpA Heatran (Red Orb) Solar Beam vs. 0 HP / 0 SpD Manaphy (Sceptilite): 168-198 (49.2 - 58%) -- 97.7% chance to 2HKO
+3 252 SpA Manaphy (Sceptilite) Ice Beam vs. 252 HP / 0 SpD Heatran (Red Orb): 123-145 (31.8 - 37.5%) -- 90.6% chance to 3HKO
Actually a workable check even against Sceptilite, though somewhat shaky when considering Stealth Rock and Heatran's difficulty keeping its health up in general.
+3 252 SpA Manaphy (Sceptilite) Ice Beam vs. 0 HP / 4 SpD Heatran (Red Orb): 122-144 (37.7 - 44.5%) -- guaranteed 2HKO after Stealth Rock
-Fully invested Blue Orb Ferro takes any +6 attack and OHKOs back with Power Whip
Not Sceptilite. +3 Ice Beam has more than a 90% chance of OHKOing, too.
-252/36 Soul Dew Latios survives +3 Ice Beam and OHKOs back with 220+ Draco (latias won't always OHKO with 252+)
I'll admit ignorance to whether people run bulky attacker Soul Dew Latios or not/it's general viability and give you this one.
-Bulkyish Venusaurite Zapdos takes anything at +3 and OHKOs back with 196+ Tbolt
I use
Sablenite Specially Defensive Zapdos, and it's not remotely reliable a counter against
Absolite Manaphy. (+3 Ice Beam and Scald both do a minimum of 76% to Sablenite Specially Defensive Zapdos, meaning if there's Stealth Rock up Zapdos loses outright) Sceptilite wins outright, at most being annoyed by Toxic.
And that's just the S down to A- mons. All of them can switch in on Manaphy and win, and if that's not required then there's a lot more which wins 1v1.
Some of them can switch in on Absolite Manaphy and
usually win. Sceptilite beats almost all of those, and aside from bulky Soul Dew Latios Blue Orb beats the remainder. (Bar Red Orb Heatran, which is shaky against Sceptilite and has other problems but is otherwise good)
Manaphy is good and sometimes can 6-0 teams ( you need at least 1 way to check or counter this beast ) after 1 tail glow. It can be deadly and normally can force some sacks, but isnt that hard to beat it , blissey can take a few hits ( if doesnt burned ) and most red orb users wall it ( if the manaphy doesnt have hp ground )
Plus manaphy suffers from 4 moves syndrome , meaning it will be always walled by something.
Actually, most Red Orb users
don't wall Manaphy. Red Orb Raikou flat-out loses to Sceptilite Manaphy, no need for HP Ground, Red Orb Hippowdon dies to Energy Ball or Ice Beam, Primal Groudon loses (252+ Atk Primal Groudon Precipice Blades vs. 0 HP / 4 Def Manaphy (Whatever): 274-324 (80.3 - 95%) -- guaranteed 2HKO), Red Orb Victini loses to Sceptilite, Red Orb Heatran is shaky against Sceptilite, Red Orb Entei loses to Sceptilite, Red Orb Arcanine loses to Sceptilite, Red Orb Azelf loses (252 SpA Azelf (Red Orb) Dazzling Gleam vs. 0 HP / 0 SpD Manaphy (Sceptilite): 218-258 (63.9 - 75.6%) -- guaranteed 2HKO vs +3 252 SpA Manaphy (Sceptilite) Ice Beam vs. 0 HP / 4 SpD Azelf (Red Orb): 172-203 (59.1 - 69.7%) -- guaranteed 2HKO), and I guess I can give you Red Orb Volcarona.
Sceptilite Manaphy tends to beat Red Orb checks that expect to beat Absolite, without even changing its moveset. Hidden Power Ground is entirely optional.
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Again, don't assume Absolite. Part of what makes Manaphy so scary is that making a
single mistake can lead to a sweep, and it's extremely difficult to find an answer to
both Absolite
and Sceptilite, making it very easy to, for instance, have your Electric type Thunderbolt Manaphy and whoops it's now +4 and sweep commences. (Blue Orb announces itself the instant Manaphy hits the field, so the only mistakes regarding it are going to be strategic -if you think your Blissey will wall Manaphy no matter what, and so allow your other Manaphy check to be KOed before ever seeing Manaphy,
then the fact that it's Blue Orb can surprise you and kill you, but you'll never have a Pokemon sitting in front of it, trying to decide what you should be doing, and lose the match right there)