My current feeling on tera is that anything less than an outright ban is insufficient. The biggest issue I have with tera is the elimination of certainties from the game. For example if I have a scarfer with a fairy move that outspeeds roaring moon then I know for a fact I can kill it, but with tera this is no longer true. This is the simplest example. but when playing several other problems presented themselves. The ability for a player in a worse endgame to completely flip it on it's head with tera is as big an issue as revenge killing offensive threats. For example in a 3v3 situation, unless I can outright win the game with my own tera it's a constant mindgame, which mon will tera, what type will it change to, and how can I react to it. This creates completely unreasonable situations for the player whose position you could normally consider comfortably better in previous gen, and essentially makes it impossible to know whether you're trading into a winning endgame or losing endgame. In my opinion it is this interaction that makes tera inherently uncompetitive.
With regard to restrictions, I think it's obvious that tera blast is a non issue, so the options are to show tera types on team preview, limit the number of tera mons per team, or limit mons to only stab teras. I think showing tera types on preview fails to address the core issue. To go back to my earlier examples, just because you know roaring moon can change types, revenge killing it doesn't become much less of a nightmare. You can argue that the change this makes is creating what is now strictly a 50/50 between using a move that kos if it teras or using a move that kos it if it doesn't tera. However this is a 50/50 that massively benefits the roaring moon player. If roaring moon predicts right it likely wins on the spot, whereas if it gets it wrong the game continues, and the opponent potentially has another 5 pokemon that can potentially beat you, in addition to having already likely traded. Additionally, while this does make endgames less guesswork, it still creates so many 50/50s that in my opinion take away from the competitive nature of the game. An example is that in previous gens I can force a 1 on 1 mu that allows me to get a kill and results in a winning position, but this becomes far more difficult if my opponent can tera to prevent this. The counter argument to this is that you have to bait the tera and determine how to win once your opponent has tera'd, however this doesn't feel like it limits tera enough to me personally, and it will still force a lot of endgames to become 20 turns of 50/50s in what should be winning positions.
The most balanced proposed restriction in my opinion is a limit to one mon that can tera per team, which is revealed on preview. However this still leads to other complications. Two of the most problematic mons I've seen with tera are dragonite and garganacl. Dragonite is a mon I used a lot myself when playing, and it won maybe 50% of my games for me. Even though you know it's tera normal, it's still far too threatening for the vast majority of teams. When paired with magnezone to trap it's best defensive check in corviknight, the only bad mu I faced with it was when I ran into 3 ghost types. Garganacl on the other hand was a bigger issue on opposing teams. I found that a lot of the time when I saw it on preview my win condition was hoping my opponent terastalised something else. The main sets I've seen are tera water and tera fighting, although tera ghost is another set I think is very good. Essentially this mon's only drawback is its typing, and when it teras the counterplay is unbelievably limited. I mention these two pokemon because I think however you restrict tera, barring restricting it to stab typing, sets like this will remain broken, and we will be forced to ban several pokemon that would otherwise be healthy in ou. Lots of people here have said stuff along the lines of what's the point of a new gen if we ban the new mechanic and new pokemon, preserving the mechanic will mean far more new pokemon will get banned than if we ban it.
The last proposed restriction is only allowing pokemon to tera to a stab type. While this solves a lot of the core issues I see with the mechanic right now, I think we'd essentially be creating a whole new cast of broken offensive threats while also essentially removing the "fun" aspects of the mechanic.
With that said, I think the two best options are as follows:
1. We ban tera outright
2. We have a suspect ladder where we try either showing all tera types on team preview, or try limiting the number of pokemon that can tera.
While I think showing tera types on preview will still fail to solve the problems created by tera, the support from the community for an option like this means I'm not opposed to trying it. I think limiting the number of pokemon that can tera is basically the solution that leaves no one happy, but it is also likely the most balanced form of the mechanic and I'm not opposed to trying it either.
With regard to restrictions, I think it's obvious that tera blast is a non issue, so the options are to show tera types on team preview, limit the number of tera mons per team, or limit mons to only stab teras. I think showing tera types on preview fails to address the core issue. To go back to my earlier examples, just because you know roaring moon can change types, revenge killing it doesn't become much less of a nightmare. You can argue that the change this makes is creating what is now strictly a 50/50 between using a move that kos if it teras or using a move that kos it if it doesn't tera. However this is a 50/50 that massively benefits the roaring moon player. If roaring moon predicts right it likely wins on the spot, whereas if it gets it wrong the game continues, and the opponent potentially has another 5 pokemon that can potentially beat you, in addition to having already likely traded. Additionally, while this does make endgames less guesswork, it still creates so many 50/50s that in my opinion take away from the competitive nature of the game. An example is that in previous gens I can force a 1 on 1 mu that allows me to get a kill and results in a winning position, but this becomes far more difficult if my opponent can tera to prevent this. The counter argument to this is that you have to bait the tera and determine how to win once your opponent has tera'd, however this doesn't feel like it limits tera enough to me personally, and it will still force a lot of endgames to become 20 turns of 50/50s in what should be winning positions.
The most balanced proposed restriction in my opinion is a limit to one mon that can tera per team, which is revealed on preview. However this still leads to other complications. Two of the most problematic mons I've seen with tera are dragonite and garganacl. Dragonite is a mon I used a lot myself when playing, and it won maybe 50% of my games for me. Even though you know it's tera normal, it's still far too threatening for the vast majority of teams. When paired with magnezone to trap it's best defensive check in corviknight, the only bad mu I faced with it was when I ran into 3 ghost types. Garganacl on the other hand was a bigger issue on opposing teams. I found that a lot of the time when I saw it on preview my win condition was hoping my opponent terastalised something else. The main sets I've seen are tera water and tera fighting, although tera ghost is another set I think is very good. Essentially this mon's only drawback is its typing, and when it teras the counterplay is unbelievably limited. I mention these two pokemon because I think however you restrict tera, barring restricting it to stab typing, sets like this will remain broken, and we will be forced to ban several pokemon that would otherwise be healthy in ou. Lots of people here have said stuff along the lines of what's the point of a new gen if we ban the new mechanic and new pokemon, preserving the mechanic will mean far more new pokemon will get banned than if we ban it.
The last proposed restriction is only allowing pokemon to tera to a stab type. While this solves a lot of the core issues I see with the mechanic right now, I think we'd essentially be creating a whole new cast of broken offensive threats while also essentially removing the "fun" aspects of the mechanic.
With that said, I think the two best options are as follows:
1. We ban tera outright
2. We have a suspect ladder where we try either showing all tera types on team preview, or try limiting the number of pokemon that can tera.
While I think showing tera types on preview will still fail to solve the problems created by tera, the support from the community for an option like this means I'm not opposed to trying it. I think limiting the number of pokemon that can tera is basically the solution that leaves no one happy, but it is also likely the most balanced form of the mechanic and I'm not opposed to trying it either.