1. Dark
Dark had to be first for obvious reasons. Even with the biggest possible level disparity, too many things here are incredibly difficult to beat. Having a moveset which covered all of them was just not possible, so Skuntank, Drapion, and Honchkrow were the hardest fights: the only recourse is to pray they show up at low enough levels that Skuntank uses Iron Tail or Flamethrower or that Drapion opts to use Acupressure a couple of times (and even then, hope it doesn't get an Attack or Defence boost). Thankfully most of the time I was able to just make it through, but the amount of flinches and critical hits you're exposed to here make it a seriously unpleasant round.
2. Poison
And then Poison next to see Skuntank and Drapion off for good. Thankfully, Earthquake makes them much easier to deal with. Crobat is annoying if it opts to Double Team on the first turn, as Psychic just narrowly falls short of a KO and you know even a single evasion boost is enough to cause multiple Shadow Sneak misses - but all you need is one Brave Bird and it'll take itself out. After initially running Protect on this build, I switched to Substitute, which not only makes Gengar a non-issue but makes Weezing a much easier fight - I lost to it more than once thanks to being outsped and flinched repeatedly by Dark Pulse. Everything else is pretty much fine.
3. Ground
Ground might seem a bit of an odd choice for the third round, and it was one I initially kept for later on. But so many foes in this round are rather too bulky - and there's not a moveset that can cover all of them. In particular I struggled a lot with Steelix, which always seemed to show up and boost too quickly with Curse for Brick Break to reliably KO it in time. This led me to change up my original strategy of using Ice Punch, instead using Ice Beam to take advantage of the generally lower Special Defence of this round's foes. Worked a whole lot better. I ran Rest instead of Protect as it gave me a far better chance of outlasting Swampert and Hippowdon (with Leftovers because not much here can hope to 3HKO Dusknoir). Predictably, I never once fought the former in either this or the Water round.
4. Ice
Ice actually isn't, on the whole, a hugely threatening round: Weavile, usually an awful foe to face, can be reliably taken out with Brick Break and Shadow Sneak as it's relatively unlikely to OHKO with Night Slash. Not much else posed an issue, so I could have left this one for a little later.
5. Ghost
And now we come to the Argenta Silver round. Always tricky, because you need to keep some versatility for the final fight. Initially I ran a more offensive moveset hoping to overwhelm whatever she brought: this was quickly shown to be a stupid idea since the first time I fought Argenta here she brought Venusaur, which promptly slaughtered me since I had no means of recovery. So I switched to a passive moveset relying mostly on Rest and Protect in conjunction with Pressure; handy against lots of things with 5 PP moves like Hydro Pump or Stone Edge. Despite my assumption that this would be a tricky round it pretty much never was.
6. Fire
Fire made sense to do next, as quite a few of the opponents faced here have the potential to be very problematic. Charizard beat me once thanks to repeated Air Slash flinches; Arcanine is overwhelmingly powerful and hard to counter; Infernape got lucky on more than one occasion with a critical-hit Flare Blitz; Heatran always manages to get the Focus Band activation; and Houndoom is just miserable to face. It might have been an idea to swap this with Ice, but ultimately sixth is still early enough for there to mostly be enough of a level advantage that it's manageable.
7. Flying
A few dangerous foes in this round but there's such a wide variety that you often get lucky and don't see them. I lost to Drifblim once after stupidly using Sucker Punch and getting it in Petaya range; Togekiss and Aerodactyl are very hard fights; and then there's Staraptor and Honchkrow, which potentially can wipe you out if they get a critical hit. For this reason, I used a Focus Sash in this round despite Dusknoir's bulk making an OHKO generally quite unlikely - actually came in handy more times than you'd think.
8. Normal
Only a few dangerous foes here. The hardest part about this round was settling on the right moveset. Initially floated using Sucker Punch and/or Toxic - the former useful when Brick Break or Ice Punch left something on a small amount of HP. Unfortunately one of the more dangerous foes here - Staraptor - isn't guaranteed to be KO'd by Sucker Punch even after taking damage from Ice Punch and Brave Bird recoil, so I found myself questioning its effectiveness before too long. Toxic seemed a good idea for some of the bulkier stuff (Regigigas, Lickilicky, Porygon2) but after doing some calcs I realised they could just be dealt with directly. Toxic also wasn't worth using against Snorlax. At lower levels, I can take a Crunch and 2HKO with Brick Break, but doing Normal this late meant that this strategy wasn't guaranteed. Instead, what works is alternating Protect and Substitute to run Crunch out of PP and then letting it Struggle to death. This would also have been a good strategy for Regigigas, except that I never actually saw it in this round.
That left Porygon-Z as the majorly threatening foe; neutralising the threat of Snorlax left me free to invest more in Special Defence. I encountered it once and unsurprisingly lost - depending on level, Dark Pulse is a 2HKO or a 3HKO, but of course you have to pray it doesn't flinch. Never saw it again after that, thankfully.
9. Rock
And it's Rock next. The given EVs ensure I outspeed and OHKO Tyranitar with Brick Break; that's pretty much the most threatening foe of this round. Don't think I ever lost to anything here.
10. Grass
The same cannot be said of Grass, a round I assumed would be incredibly easy. Not so. Quite a few things here unexpectedly caught me out - Exeggutor flattened me with a Liechi-boosted Wood Hammer once, Shiftry is a gigantic pain in the neck, and Ludicolo can be very annoying if it's not poisoned quickly. I kept thinking I should move this back a couple of places but ultimately there just wasn't an earlier type I could make the switch for. Bulky as Dusknoir is, it's outsped by a lot of equally bulky mons here.
11. Electric
I never look forward to this round but surprisingly this actually wasn't bad. The most threatening of the bunch is Rotom which, like Exeggutor, can eviscerate with a Petaya boost if hit too hard. Damage calculations are vital here to check yourself, so often the best way to go was Shadow Sneak first turn, Sucker Punch the next. Lum Berry seemed the obvious item choice, but I'm outsped by everything anyway so Leftovers made more sense as a way of giving me a little more breathing room against those foes not equipped with a super-effective move (Lanturn, Luxray, Jolteon, Ampharos, et al).
12. Water
My expectation was that this would be a hard one, too - but for the most part, it wasn't. Ultimately that was more down to dumb luck than anything else - every time I did this round, I fought weak NFEs all the way up to battle 8 or 9 and then had a good matchup for the final couple of fights. Milotic is an absolute joke of a fight, Feraligatr and Lapras are easily dealt with, and Suicune is trivially easy. Wailord gave me a good fight on one occasion (I'd completely forgotten Sleep Talk can call moves which are out of PP and got smacked by a full-power Water Spout), and Kingdra is more than a little difficult, but I didn't lose to either of them. Sharpedo might have given me a little trouble if it had shown up; I didn't ever see Swampert, Blastoise, or Empoleon. The only thing I ever lost to here was Starmie when it disgustingly got two consecutive crits on Hydro Pump. I lost to Slowbro once when Argenta used it, which made me wary of seeing it again - however, I fought it several times here and in the Psychic round and never had trouble with it again.
13. Psychic
This should, by rights, have been a round I could leave right until the very end, but the presence of several foes I'd previously lost to (Exeggutor, Starmie, Slowbro) compelled me to do it next. On the whole this was a very easy round, though I lost once, frustratingly, to Medicham of all things, which got one evasion boost and promptly dodged all subsequent attacks, 2HKOing me with Psycho Cut thanks to the second move getting a critical hit. Metagross was a foe I was nervous about facing, but I never once saw it here or in the Steel round. Fought Uxie and Cresselia and I believe Argenta once beat me with Azelf, but no appearances from the Lati twins (as so often happens).
14. Dragon
An often very straightforward round. Pretty much the only threatening foe is Kingdra, which beat me very capably one time. This made me realise that the optimal item here was Lum Berry (not Leftovers) since it pretty much always goes for Yawn first turn. For this round, I made use of the rest exploit and on my winning streak hilariously ended up fighting Altaria not once but three times.
15. Steel
I did question the sense of leaving this one so late. Forretress is a potentially difficult foe thanks to Payback's high damage and its held Lum Berry meaning it needs burning twice - but Dusknoir outspeeds, and for some reason when I fought it it seemed prone to using Bug Bite more often than Payback. Weird. Skarmory could have been troublesome, and I was already wary of Metagross - thankfully neither appeared. I had trouble with Aggron and came very close to a loss after missing with Will-o-wisp twice and taking a crit Stone Edge - but Iron Tail's terrible accuracy saved me, and I was able to clinch a win. Lucario would have been a joy to fight but sadly I didn't get that lucky.
16. Fighting
Pretty much the only round I could call incredibly easy. The given EVs ensure I outspeed Machamp and 2HKO with Psychic - otherwise, it could use Foresight and then Dynamicpunch. Hariyama was the only really problematic foe - in the end, rather than hope to 2HKO, I went with the PP-wasting strategy I used for Snorlax, combining Substitute and Protect to use up all of its Payback PP and be more safely able to deal with it. At least that's what I would have done had I encountered it - but that never happened. Nor did I encounter Machamp. Oh, well.
17. Bug
That left me with Bug as the final round. A very reasonable choice since Dusknoir resists Bug and only a couple of foes here pose a genuine threat. After initially deciding to run Fire Punch, I considered what might be a better choice for Argenta's gold fight was Substitute. Sure, Fire Punch is decent enough coverage but there's so few things I could actually beat with it - better to trust to Pressure stalling against the vast majority of foes. Yanmega is the most dangerous to face, since burning it won't compromise its offenses - with Tinted Lens, it's truly dangerous. Thankfully, my round 9 fight was Scizor - burn as it SDs, Substitute as it SDs again, then Protect and Sub over and over, Rest as it breaks the last sub, and by then it's fainted. Nice and simple.
Argenta Gold
I sweated a bit over this one. There were a lot of things she could have brought that would have been downright unbeatable. Ultimately, she brought... Metagross. Well, that's not the mon I was hoping for but it's possible to beat. I dithered over my first move - Substitute or Will-o-wisp? - and correctly predicted she'd set up Light Screen first turn. My Will-o-wisp hit and I was able to set up a Substitute next turn. From there, it was a relatively straightforward dance of Protect-Sub-Protect-Sub-Protect, using Rest as it broke my final sub. By then, it was out of Meteor Mash PP and Zen Headbutt wasn't capable of breaking a sub in a single turn - but it's irrelevant, as that was enough time for the burn to do its job and faint it.
Unfortunately after 170 I didn't last very long at all. Chose Fighting-Bug-Psychic-Ice-Grass and lost to a Tangrowth which got a critical hit Grass Knot as I tried to Substitute, leaving me too weak to Sub and promptly outsped and KO'd next turn.
Streak submission - 48 wins, Level 50 Platinum Battle Factory (physical cartridge)
Friends...there is no more painful a way on God's green earth to lose a streak than reaching gold-print Thorton, being told he is a Steel-primary user, picking Flygon4 as your lead alongside Heracross4 and Weavile4, OHKO-ing his Megnezone lead, and then running into Hippowdon. Curse, Slack-Off Hippowdon. And just slowly watching as a 20+ turn battle proceeds without you landing a single crit, freeze, or anything you need to stop the inevitable loss that would otherwise have been an easy victory.
Truly I can match this - on the attempt directly before my successful winning streak, Argenta used Blaziken against me for the silver match, which I confidently assumed would be a very easy win since it can only touch Dusknoir with Blaze Kick. All I have to do is stall for 5 turns until it's out of PP, right? And then the first hit that connects gets a critical hit, and down I go. I swore very, very loudly.
