Here are my thoughts on the questions concerning stall in this meta:
- What are the roles of Pokemon that were essential to your stall team's success? Rapid spinning was very important, especially having a spinner that could get a spin off reliably against deo-d + gengar strategies. A revenge-killer that is able to revenge boosted threats was super valuable, as stall teams often are prone to set-uppers sweeping them. A scarfed trick user was extremely helpful as well as a kind of emergency button.
- What was the most useful Pokemon in your team and why? Scarftios probably ended up being the single most valuable pokemon on my team, as it basically either got off a trick, revenged a threat that otherwise would have swept the team, performed a mini-sweep in the endgame, or some combination of the above.
- What were the biggest threats to your stall team, and how you dealt with them? The biggest threats were pokes that are difficult to truly counter--such as terrakion, genesect, and tornadus-t--I was forced to play around them instead of being able to go to a sure-fire counter. This is one of the reasons why latios was so important for the team.
- Did you find it easy or difficult to build a successful stall team? Explain why.
The initial process felt fairly easy--I knew I wanted to use rain stall, so toed was a given. The other early members (tentacruel, jirachi, gastrodon) fit in very quickly. The hard part was deciding on the last members, which were primarily there to cover the holes in the team--latios against set-uppers and celebi against status as well as some specific threats, such as breloom and keldeo.
- How did you reach the Hall of Fame? Was it easy or difficult? Did having a stall team benefit you? What advice would you give to those laddering with stall teams?
The good thing about a well-constructed stall team is that it tends to be very solid making laddering consistently easier. On the other hand, battles tend to take longer, meaning that the going is slower than with an offensive team. If you get used to playing with the team though, you can ladder pretty quickly though.
EDIT: Also, thanks for the team comments alexwolf. I've never really thought about thunder on latios, but it definitely seems like a very valid option. Psyshock is nice though for hitting the blobs harder, especially if I've tricked away their eviolite/leftovers. Also, without psyshock subCM keldeo can pretty much 6-0 the team. I'll definitely give thunder a try though.
Toxic on cruel is an idea, but I really love the scouting protect gives, as well as the extra recovery. I have toxic on a couple pokes already, and sub + protect is actually really nice on cruel. Toxic is a definite option though, and might be worth it if only to beat jellicent.
Kyurem-B has been fairly low-key in the matches I've played against him--nothing can survive a couple banded outrages, but on the other hand latios just comes in and OHKOs (with SR at least). Sub sets can be problematic, but jirachi works well at taking anything except for banded fusion bolts. One poke that has been very threatening is subsalachomp, which really can sweep pretty much the whole team if it gets to set up. I've considered putting HP [ice] on celebi to serve as a better chomp counter in general, but can't find the moveslot and don't really want to replace psychic--any thoughts? I find celebi suffers a ton from 4MSS.