- Against what do you bring Forretress in?
Stall mons like Skarm and Miltank are your best bets. Steelix doesn't hit you too hard either. You can also bring it in on Lax, Nido, and Egg after you've scouted their sets, but the annoying thing is that you have to respect the possible OHKO until they do reveal their sets. Oh, and Toxic-Pursuit Charmbreon is a similar sort of beast, only instead of threatening with Fire moves, it threatens with ML BP.
- What partners well with Forretress?
Well, once Spikes are down, pretty much everything. If you're using Forry, though, you are 100% committing that slot to Spikes and the unique advantages Forry has over Cloy in that regard, so you really wanna load up on players of the Spikes game, and generally you will end up with a pretty stally sort of team. You can pair it with Missy for spinblock, Gengar for spinblock if you run HP Bug (as Forr takes care of Starmie itself in that case), maybe a Pursuiter (Ttar is the most obvious one, Houndoom is loads of fun, and Umbreon is weak but can just come right on in without fearing Surfs). There's some mons that are especially good at capitalizing off of Spikes, too: Roar Raikou, Nidoking, and Exeggutor are a couple examples, although you'll probably only fit one (if lucky, two) on your team. I find that I typically also want a Suicune on a Forry team, as generally the mon you have playing the Spikes game can help you out vs. Grounds, but you don't really get that with Forry.
- Forretress + Skarm feels really wrong to me, but Forretress isn't an adequate answer to QuakeCurseLax. How do you deal with that?
Adding another Steel to a Forry team is not inherently redundant, as Forry just sets spikes and doesn't exactly counter anything anyway. So you can go ahead and add that Skarm (or even a Steelix, who's also a pretty nice Spikes shuffler). That said, it tends to feel wrong to me too, so I use stuff like Rhydon/Ttar/Umbreon/Miltank/Misdreavus to deal with Lax. EQ Curselax can be annoying, yes, but not insurmountable.
- What movesets work well on Forretress, and in what contexts?
Forr isn't terribly complicated, this is its main set:
Spikes/Rapid Spin/Explosion/Mystery Move
Toxic is probably the best general-purpose 4th move, as it lets you actually keep Cloyster out of your face, punish Missy spinblock, and maybe even force a Curselax to Rest or keep a Rhydon from switching in willy-nilly. HP Bug will shoo Starmie away. HP Ghost is on the upper end of 3HKO on Gengar and Misdreavus, so nice for stopping spinblock. HP Fire solves the Forretress ditto problem. We're getting into the bottom of the barrel now, but wihle Reflect won't help you much with the Spikes game, it's still a good move in general (replacing Rapid Spin with Reflect isn't out of the question either). Rest is also possible if you wanna use it to tank Nidos or Eggs or something. Some SPLers are also hyping Giga Drain, which I think is just stupid because you still need to run Toxic on top of it to beat Cloy, but it's there.
There's also this kinda gimmicky set intended to stall Lax if you really feel like you need it to do that:
Spikes/Rest/Defense Curl/???
where ??? is an attack (e.g., HP Bug), Toxic, Rapid Spin, Explosion, or shit, even Sleep Talk. You could run Curse over DCurl if you choose to use Boom or HP Bug. You might also be able to stall mono-Lax with Reflect over DCurl (+5 DE behind Reflect is 24-28%, unlikely 2HKO at 48-57% without Reflect up), but you have to be real smart about when you Rest, and EQ Curselax is almost definitely too dicey (2HKO without Reflect up, 27-32% with it up). Sleep Talk could make it less dicey though.
- What real advantages does Forretress have over Cloyster? I've seen mentions of HP Bug and thus holding Spikes vs. Starmie, but now Borat's talking about HP Ghost Forry; what does HP Ghost Forry have over Cloyster? (they both have 3HKOs on the Ghosts)
Forry is immune to Toxic, so it lasts longer vs. stalls. Forry can run both Rapid Spin and Explosion. Those are its chief advantages over Cloy. HP Bug for Starmie is nice, but Misdreavus + Toxic can work perfectly fine there, too, so that's hardly a chief advantage. HP Ghost is more for just stopping spinblock if you can afford to run it as your 4th.
Here's a more-or-less standardish Forry mega-stall team:
Forretress - Toxic/Spikes/Rapid Spin/Explosion - maybe HP Ghost over Toxic to stop Gengar spinblock, or HP Fire to really stick it to other Forrys.
Misdreavus - Mean Look/Psong/Protect/Confuse Ray - not really much room for flexibility here. Keep it clear of Toxics if you can.
Snorlax - Double-Edge/Fire Blast/Earthquake/Rest - Maybe Toxic over EQ. Needs to be a mixlax, otherwise you have literally zero instant offense.
Raikou - Thunder/HP Ice/Roar/Rest - Reflect could go over HP Ice.
Suicune - Surf/Toxic/Rest/Sleep Talk - Ice Beam over Toxic for better talks vs. Marowak.
Umbreon - Pursuit/Toxic/Charm/Rest - a ML Pass set might do work if you can get Skarms to Rest, but Pursuit is handy for Gengars.
I'm not terribly high on this sort of team because I think it just doesn't run enough attacks. I've attempted using Gengar and Rhydon on a team like this, to... eh, fairly mediocre results actually. The idea is mostly to stall, stall, stall, secure in the knowledge that Forry + Missy all but guarantee endgame Spikes for you.
I've also seen more aggressive teams on PO that use Forry (user Kururin, for example). He uses its ability to survive a STAB Thunder to play it like a suicide hazards lead, which is kinda weird, but actually kinda works with Gengar spinblock + explosion pressure everywhere making spinning pretty difficult.
