If you're talking about the Halloween event, here's what I found:
Best Darkrai Counters
Conkeldurr - Counter Dynamic Punch
Lucario - Counter Aura Sphere
Beedrill (Mega) - Bug Bite X Scissor
Machamp - Counter Dynamic Punch
Togekiss - Charm Dazzling Gleam
Hariyama - Counter Dynamic Punch
Heracross - Counter Megahorn
Toxicroak - Counter Dynamic Punch
Volcarona - Bug Bite Bug Buzz
Breloom - Counter Dynamic Punch
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As for what to do once you've found a raid, Darkrai is a dark-type, so its weaknesses are fighting, fairy, and bug-type Pokemon. Machamp is a strong choice if going with a fighting-type, especially if it knows counter and dynamic punch. Lucario and Terrakion are also good choices should you have those Pokemon at your disposal.
Trainers with strong bug-types will want to bring Heracross and Scizor into the mix if they can, especially if Scizor knows X-Scissor. As for fairy-types, Granbull and Togekiss are strong options providing they know dazzling beam. Gardevoir is good too, but something of a double-edged sword. Although its fairy half will do damage to Darkrai, whereas its psychic half will be weak against the dark-type Pokemon.
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Best Darkrai counters are strong Fighting and Fairy types, such as Machamp, Togekiss, Hariyama, Heracross, Toxicroak, Breloom and Gardevoir. Darkrai is weak to Fighting, Fairy, and Bug type moves. Darkrai is boosted by Fog weather.
Pokemon GO Conkeldurr
Conkeldurr
Counter Dynamic Punch 686.5s 30
Pokemon GO Lucario
Lucario
Counter Aura Sphere 628.5s 38
Pokemon GO Beedrill (Mega)
Beedrill (Mega)
Bug Bite X Scissor 665.6s 39
Pokemon GO Machamp
Machamp
Counter Dynamic Punch 706.3s 34
Pokemon GO Togekiss
Togekiss
Charm Dazzling Gleam 799.6s 26
Pokemon GO Hariyama
Hariyama
Counter Dynamic Punch 757.1s 34
Pokemon GO Heracross
Heracross
Counter Megahorn 781.2s 33
Pokemon GO Toxicroak
Toxicroak
Counter Dynamic Punch 773.6s 37
Pokemon GO Volcarona
Volcarona
Bug Bite Bug Buzz 784.9s 38
Pokemon GO Breloom
Breloom
Counter Dynamic Punch 724.2s 45
Pokemon GO Meloetta (Pirouette)
Meloetta (Pirouette)
Low Kick Close Combat 792.3s 29
Pokemon GO Keldeo (Ordinary)
Keldeo (Ordinary)
Low Kick Close Combat 825.5s 34
Pokemon GO Keldeo (Resolute)
Keldeo (Resolute)
Low Kick Close Combat 828.3s 34
Pokemon GO Blaziken
Blaziken
Counter Focus Blast 782.1s 43
Pokemon GO Granbull
Granbull
Charm Play Rough 828.9s 39
Pokemon GO Kyurem (White)
Kyurem (White)
Dragon Breath Focus Blast 815.1s 40
Pokemon GO Gardevoir
Gardevoir
Charm Dazzling Gleam 804.8s 44
Pokemon GO Charizard (Mega Y)
Charizard (Mega Y)
Fire Spin Blast Burn 850.3s 39
Pokemon GO Darmanitan (Galarian Zen)
Darmanitan (Galarian Zen)
Tackle Super Power 779.2s 48
Pokemon GO Emboar
Emboar
Low Kick Focus Blast 829.4s 42
Pokemon GO Yanmega
Yanmega
Bug Bite Bug Buzz 840.5s 42
Pokemon GO Genesect (Shock)
Genesect (Shock)
Fury Cutter X Scissor 809.4s 46
Pokemon GO Pinsir
Pinsir
Fury Cutter X Scissor 828.5s 45
Pokemon GO Genesect (Burn)
Genesect (Burn)
Fury Cutter X Scissor 810.7s 46
Pokemon GO Genesect (Chill)
Genesect (Chill)
Fury Cutter X Scissor 812.2s 46
Pokemon GO Genesect
Genesect
Fury Cutter X Scissor 813.1s 47
Pokemon GO Genesect (Douse)
Genesect (Douse)
Fury Cutter X Scissor 813.6s 48
Pokemon GO Sawk
Sawk
Low Kick Focus Blast 840.1s 44
Pokemon GO Meloetta (Aria)
Meloetta (Aria)
Quick Attack Dazzling Gleam 890.9s 39
Pokemon GO Cobalion
Cobalion
Metal Claw Sacred Sword 900.6s 37
Important note: Prioritize Gardevoir and Togekiss versus Focus Blast. Fairy types take reduced damage from Fighting and they perform better than Machamp and Hariyama.
As we’ll go in-depth in the next section (moves breakdown), 60% of Darkrai’s move pool consists of DARK moves, which means that 60% of time Darkrai deals reduced damage to Fighting and Fairy types.
Taking reduced damage converts into more opportunities to activate charge moves, and in turn, into more damage. Hence why Machamp, Togekiss and Hariyama rule the top 3 spots. Once Conkledurr gets released, it will be an amazing Darkrai counter as well, but for now this is the list.
Charge moves
Darkrai’s move pool is consistently easy to counter, provided that you have appropriate Pokemon at your disposal:
If Darkrai has Dark Pulse, you should prioritize Fighting types. They take reduced damage and easily land charge moves regardless of dodging. In order not to waste Revives, be careful with squishy ones like Breloom.
Versus Focus Blast you should always prioritize Gardevoir and Togekiss. Due to their dual typing, they take 2x reduced damage from Focus Blast. Gardevoir and Togekiss are best counters to Darkrai when it has Focus Blast.
Treat Shadow Ball in the same way like Dark Pulse and use Fighting types. Do not use Gardevoir as it takes increased damage from Ghost moves and will melt easily.
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Hope this helps! :)
