With the results of MCS XVI giving valuable insight into the new meta, we have multiple major changes to the Tier List.
Ancient Gears were by far the most played deck in the MCS and converted that into very high representation in the Top 32 as well. Ancient Gears were the deck with the biggest target on its back, having to fight through main-decked Skull Meister and Bad Aim, side-decked System Down, a resurgence of Amazoness and Hero decks using Amazoness Queen and Cosmic Cyclone respectively, and even Koa'ki players who took advantage of being under the radar to win the whole event. One of the biggest takeaways from the MCS was the return of Koa'ki, and Ancient Gear decks will again need ways to deal with them consistently or risk falling back to Tier 2.
Ancient Gears stand strong in Tier 1 despite the large target on their back and players running counter cards like Skull Meister en masse. This deck has consistently been the most represented in both swiss and top cut, and has impacted the way others build their decks around it as a result of that presence.
Koa'ki Meiru has been promoted to Tier 2. Although weaker than in its pre-banlist form, Koa'ki Meiru is still stronger than many expected and took advantage of an over-correcting meta to win the MCS. Many decks dropped Paleozoic Canadia and Floodgate Trap Hole for Skull Meister and Bad Aim, neither of which do much against Koa'ki's offensive onslaught. One interesting thing to watch will be the balancing act between Koa'ki and Ancient Gears: Which deck is considered more of a threat by other players? Are the main-decked Skull Meisters worth it if you're still losing to Koa'ki? And conversely, is Canadia worth putting back into the deck to deal with Koa'ki, given how little it does to stop Ancient Gears?
Amazoness and Heros have been promoted to Tier 2 (from off the Tier List) after significant representation in the MCS as strong counters to Ancient Gears. However, a corresponding rise in the number of Koa'ki Meiru decks may be problematic for these decks which had consistently struggled to be competitive pre-banlist. On the other hand, Amazoness and Hero decks are some of the best abusers of Bad Aim and can deal with Ancient Gears well, so as long as Ancient Gears are the deck to beat, expect these decks to be doing just that.
Finally, Dinos have been demoted to Tier 2. Hurt by many of the same counters that hit Ancient Gears (mainly Skull Meister), Dinos are also not happy to see the return of Koa'ki or Amazoness. But as another strong counter to Ancient Gears (when maxed out on Skull Meister and Bad Aim), Dinos will also be a viable competitive choice as long as Ancient Gears remain in the meta.
Though Dinosaurs are still a top contender and a fantastic deck, it is evident that it is represented far less than Ancient Gear within tournaments. This demotion is a reflection of this.
Amazoness make a strong resurgence into Tier 2 after a lot of time spent off the tier list. This deck is very versatile and right now has a toolbox of answers to a majority of the meta between its abundance of backrow, its reflected battle damage with Amazoness Swords Woman, and its ability to stall by sitting on on Amazoness Queen.
Heroes also make their way onto the Tier List at Tier 2 thanks to their well known ability to access quick OTKs in a meta that has otherwise slowed down.
Karakuri remains in Tier 3, with the ability to deal with many threats in the meta. A very poor Ancient Gear match-up holds the deck back and dictates most of the Karakuri player's side deck. If Canadia and Floodgate come back for Koa'ki, this deck's position will be even worse, although Bad Aim is already difficult to play through since Karakuri Merchant mdl 177 "Inashichi"'s mandatory search will always give your opponent a window in which to destroy your Karakuri Komachi mdl 224 "Ninishi".
Karakuri can easily take games by popping off into its explosive combos. However, it can just as easily lose to itself. It is still too early in the format to accurately determine where every deck falls into place, but a Tier 3 status feels accurate for Karakuri based on its recent tournament performances.
Buster Blader and Vampires have been removed from the Tier List. Buster Blader's best skill, Last Gamble, was heavily nerfed and their worst match-up is the sole Tier 1 deck. Vampires have similiarly lost at least partial access to their best skill, KaibaCorp Bling, and are incredibly weak to a meta dominated by tech cards like Skull Meister and Bad Aim.
Buster Blader so far has failed to return to the metagame. This may be due to it not yet being optimised, and it also doesn't help that its worst matchup is sitting at a Tier 1 position. For the time being, a demotion for Buster Blader is suitable.
Vampires unfortunately fall from the Tier List. There are too many elements in the meta that are indirectly countering it. It is hard to justify playing Vampires in tournaments at the moment when there is no evident advantage you get from doing so.
Vampires fall off the Tier List entirely due to a mix of having Samurai Skull limited to 2 and the large presence of Skull Meister in the current meta. Between losing access to simultaneously having 3 Samurai Skull with 2 Enemy Controller, and most players running cards that directly counter the deck, Vampires unfortunately don't stand a chance right now.