Gengar gets Trick in Pokemon Platinum, from one of its many Move Tutors. Though TrickZam is faster, and is more likely to get away with a Modest nature after it discards its scarf, it lacks Gengar's movepool to be a ridiculously potent threat. This post is going to analyse the matchups of said Gengar and show what it can actually do in a proper analysis.
Let's start with Gengar vs current common leads, as we know this Gengar will be almost exclusively used as a lead or revenge killer.
Azelf: Focus Sash variants with Psychic or Shadow Ball win, all others can do nothing but switch out of Shadow Ball. Hypnosis can still counter the former, but forces Gengar out after the sleep.
Bronzong: Trick users generally do very well against Bronzong; Bronzong with a scarf is largely useless.
Other Gengars: Shadow Ball; anything without a sash loses; Sash still wins this matchup.
Deoxys-S: Impossible for Deoxys to outspeed the Timid version, and bulky lead variants rarely if ever carry Focus Sash. The real question is: does Timid Gengar have enough oomph from Shadow Ball to OHKO?
Calm 252/252 Deoxys-E (you'll likely never see this) takes 67.76-79.93.
More common Timid or Modest 252/0 is OHKOed a bit over half the time
Note that Modest Scarf Gengar outruns all but Timid Deoxys-E with almost max speed, and almost no leads currently outrun max speed. This _will_ however change with Gengar around, so Deoxys-E with max speed becomes a risk IF it packs Psychic. Remember that a lot of lead Deoxys-E don't even carry Psychic, making this a moot point.
Dusknoir: An occasional lead in Trick Room teams, Dusknoir can Shadow Sneak to outrun Gengar, but note that even 252 Attack Brave Dusknoir (very rare) on minimum Gengar will not OHKO, and it will end up stuck with a scarf it very much does not want to wear.
Gyarados: Thunderbolt, nuff said? Gyarados can do nothing but switch out of Gengar, as always.
Hippowdon: Rare, but worth some consideration here as Gengar can only potentially harm it with HP Ice, and won't do terribly much. Standard Hippowdon's Stone Edge will 2hko with sandstorm unless it misses, a significant 36% chance in two turns that at least one will miss. This, at the very least, says Gengar can let itself be dented and stick the typically useful wall with a choice scarf, ruining it. The worst that can happen back is it steals a Choice Band, which it can just drop off on something else later.
Jolteon: Another rare lead, and one that can cannot ohko Gengar even with Shadow Ball: modest 252 jolteon can only manage 98.09 unless it packs Specs. The question is what Gengar should do to it back: Shadow Ball is a 2hko, and it can outspeed with Choice Scarf, but it will be so low that Stealth Rock will finish it later if it ever goes up. Tricking a Choice Scarf onto most Jolteons is effective; at the very least it means if they WERE packing specs, you're alive and not dead, and can get out and use the specs later. Jolteon is a somewhat effective lead against Gengar, but it's still a 5-5 matchup at best, in a world of 10/0s.
Anti-Lead Machamp: Honestly, I think Machamp wins this matchup handily. Even packing Psychic, Gengar can't do much to it. Gengar has to bail out, giving Machamp a free sub and being a serious pain to a team. This really shows how effective this set is in the current metagame: the funny thing is how many standards in format2 beat the crap out of it. ;)
Metagross: Agiligross or Support gross generally lead, and neither like being stuck with a Scarf. They will likely trade being fouled with KOing Gengar, but unless Metagross runs at least 234 speed, Timid Gengar will outspeed it even with a scarf (to throw Hypnosis at it, if it packs it), and getting stuck on Agility or Stealth Rock is definitely a bad thing. This isn't an outright win, but it usually takes the wind out of its sails.
Roserade: A lead we haven't seen in a long time, and gets outsped and smacked around by shadow ball or HP Ice. If Gengar packs Hypnosis over HP Ice, it could also be put to sleep. Roserade's best option if not switching out is Sleep Powder; Gengar has an option here to take the sleep and Trick, sticking Roserade on sleep powder while Gengar switches out or tries to wake itself.
Spiritomb: Good old Lead Tomb is still screwed; Sucker Punch doesn't stop Trick, and it's not fast enough to taunt. It's going to get stuck with a scarf, do not much to Gengar, then Gengar will either sleep Tomb and get away, or die to the second Pursuit, as it's a 2hko even without a switch, so a 7-3 auto-win for Gengar, or a marginal victory every time.
Tyranitar: Another common lead, this is where Gengar has to consider Focus Blast vs HP Ice vs Hypnosis. Focus Blast and Hypnosis are both 70% answers to T-Tar, the latter being more versatile but forcing you to switch out as you're stuck on Hypnosis. Note that Boah and Lead Tar don't typically pack Pursuit, either; you're often free to switch out, which may well be your answer here. Avantage T-Tar.
Yanmega: This guy really doesn't like Gengar leads in general, but ones it can't outspeed are much worse. Thunderbolt always OHKOs so it really doesn't have anything to do but switch out. You also have the option of sticking it with a scarf, but this IMO is overkill. Better to force it out and let the impending doom of stealth rock and your Gengar still being alive take care of it.
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Let's see what the typical format2 leads do to it, that we haven't already covered?
Abomasnow: Most A-Snow leads really don't like being scarfed, but Gengar doesn't typically like getting hit with Blizzard. This is Gengar's win, but not without taking a huge dent. Even with 252 special attack, though, Blizzard doesn't KO minimal Gengar. The worst you can do is end up against a scarfsnow, Trick, and get yourself forced out/dented. Scarfsnow leads are very rare, though.
Alakazam: TrickZam outspeeds only if it's Timid, but if it is, goodbye Gengar, Psychic is an easy OHKO. If it's not, Shadow Ball reverses the role. 50/50 matchup.
Flygon: Lead Flygon is scarfed, outsped by Gengar, and OHKOed by HP Ice. If it doesn't pack HP Ice, though, Draco Meteor flattens Gengar like a pizza.
Hippopotas: See Hippowdon, but HP Ice OHKOs.
Staraptor: Scarfraptor leads are outsped and OHKOed by thunderbolt.
Final Analysis
I think we probably have a broken pokemon with:
Trick
Shadow Ball
Thunderbolt
Hidden Power Ice/Hypnosis
Anybody else have anything to say?
Let's start with Gengar vs current common leads, as we know this Gengar will be almost exclusively used as a lead or revenge killer.
Azelf: Focus Sash variants with Psychic or Shadow Ball win, all others can do nothing but switch out of Shadow Ball. Hypnosis can still counter the former, but forces Gengar out after the sleep.
Bronzong: Trick users generally do very well against Bronzong; Bronzong with a scarf is largely useless.
Other Gengars: Shadow Ball; anything without a sash loses; Sash still wins this matchup.
Deoxys-S: Impossible for Deoxys to outspeed the Timid version, and bulky lead variants rarely if ever carry Focus Sash. The real question is: does Timid Gengar have enough oomph from Shadow Ball to OHKO?
Calm 252/252 Deoxys-E (you'll likely never see this) takes 67.76-79.93.
More common Timid or Modest 252/0 is OHKOed a bit over half the time
Note that Modest Scarf Gengar outruns all but Timid Deoxys-E with almost max speed, and almost no leads currently outrun max speed. This _will_ however change with Gengar around, so Deoxys-E with max speed becomes a risk IF it packs Psychic. Remember that a lot of lead Deoxys-E don't even carry Psychic, making this a moot point.
Dusknoir: An occasional lead in Trick Room teams, Dusknoir can Shadow Sneak to outrun Gengar, but note that even 252 Attack Brave Dusknoir (very rare) on minimum Gengar will not OHKO, and it will end up stuck with a scarf it very much does not want to wear.
Gyarados: Thunderbolt, nuff said? Gyarados can do nothing but switch out of Gengar, as always.
Hippowdon: Rare, but worth some consideration here as Gengar can only potentially harm it with HP Ice, and won't do terribly much. Standard Hippowdon's Stone Edge will 2hko with sandstorm unless it misses, a significant 36% chance in two turns that at least one will miss. This, at the very least, says Gengar can let itself be dented and stick the typically useful wall with a choice scarf, ruining it. The worst that can happen back is it steals a Choice Band, which it can just drop off on something else later.
Jolteon: Another rare lead, and one that can cannot ohko Gengar even with Shadow Ball: modest 252 jolteon can only manage 98.09 unless it packs Specs. The question is what Gengar should do to it back: Shadow Ball is a 2hko, and it can outspeed with Choice Scarf, but it will be so low that Stealth Rock will finish it later if it ever goes up. Tricking a Choice Scarf onto most Jolteons is effective; at the very least it means if they WERE packing specs, you're alive and not dead, and can get out and use the specs later. Jolteon is a somewhat effective lead against Gengar, but it's still a 5-5 matchup at best, in a world of 10/0s.
Anti-Lead Machamp: Honestly, I think Machamp wins this matchup handily. Even packing Psychic, Gengar can't do much to it. Gengar has to bail out, giving Machamp a free sub and being a serious pain to a team. This really shows how effective this set is in the current metagame: the funny thing is how many standards in format2 beat the crap out of it. ;)
Metagross: Agiligross or Support gross generally lead, and neither like being stuck with a Scarf. They will likely trade being fouled with KOing Gengar, but unless Metagross runs at least 234 speed, Timid Gengar will outspeed it even with a scarf (to throw Hypnosis at it, if it packs it), and getting stuck on Agility or Stealth Rock is definitely a bad thing. This isn't an outright win, but it usually takes the wind out of its sails.
Roserade: A lead we haven't seen in a long time, and gets outsped and smacked around by shadow ball or HP Ice. If Gengar packs Hypnosis over HP Ice, it could also be put to sleep. Roserade's best option if not switching out is Sleep Powder; Gengar has an option here to take the sleep and Trick, sticking Roserade on sleep powder while Gengar switches out or tries to wake itself.
Spiritomb: Good old Lead Tomb is still screwed; Sucker Punch doesn't stop Trick, and it's not fast enough to taunt. It's going to get stuck with a scarf, do not much to Gengar, then Gengar will either sleep Tomb and get away, or die to the second Pursuit, as it's a 2hko even without a switch, so a 7-3 auto-win for Gengar, or a marginal victory every time.
Tyranitar: Another common lead, this is where Gengar has to consider Focus Blast vs HP Ice vs Hypnosis. Focus Blast and Hypnosis are both 70% answers to T-Tar, the latter being more versatile but forcing you to switch out as you're stuck on Hypnosis. Note that Boah and Lead Tar don't typically pack Pursuit, either; you're often free to switch out, which may well be your answer here. Avantage T-Tar.
Yanmega: This guy really doesn't like Gengar leads in general, but ones it can't outspeed are much worse. Thunderbolt always OHKOs so it really doesn't have anything to do but switch out. You also have the option of sticking it with a scarf, but this IMO is overkill. Better to force it out and let the impending doom of stealth rock and your Gengar still being alive take care of it.
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Let's see what the typical format2 leads do to it, that we haven't already covered?
Abomasnow: Most A-Snow leads really don't like being scarfed, but Gengar doesn't typically like getting hit with Blizzard. This is Gengar's win, but not without taking a huge dent. Even with 252 special attack, though, Blizzard doesn't KO minimal Gengar. The worst you can do is end up against a scarfsnow, Trick, and get yourself forced out/dented. Scarfsnow leads are very rare, though.
Alakazam: TrickZam outspeeds only if it's Timid, but if it is, goodbye Gengar, Psychic is an easy OHKO. If it's not, Shadow Ball reverses the role. 50/50 matchup.
Flygon: Lead Flygon is scarfed, outsped by Gengar, and OHKOed by HP Ice. If it doesn't pack HP Ice, though, Draco Meteor flattens Gengar like a pizza.
Hippopotas: See Hippowdon, but HP Ice OHKOs.
Staraptor: Scarfraptor leads are outsped and OHKOed by thunderbolt.
Final Analysis
I think we probably have a broken pokemon with:
Trick
Shadow Ball
Thunderbolt
Hidden Power Ice/Hypnosis
Anybody else have anything to say?
