Bulletproof: Originally this was my top choice, and while other options have grown on me more, I still think this has plenty of merit to it. I disagree with Agile Turtle's comment about the ability being potentially anti-concept, as there really aren't any Pokemon that we are suddenly able to beat with this typing that our typing would imply otherwise. Almost every relevant Fighting-type in the tier is a physical attacker who couldn't care less about Bulletproof, and the only relevant Fighting-type in the tier that runs a special attacking set, Iron Valiant, doesn't even run fighting-type coverage on those sets. Furthermore, I think that solidifying our matchup into Gholdengo, as well as easing our matchups into other threats such as Darkrai (Who often runs a fair number of moves that are blocked by this) is a very solid benefit and a reason to consider this. I also heavily disagree with Imw0rstadP0keM0n's comment about how Poison-types would switch to Sludge Wave, as it's a significantly worse move than Sludge Bomb, and I really don't think they are going to opt for a worse move just for this one match-up in most cases due to the opportunity cost.
Misty Surge: This ability is a pretty big a double-edged sword. On one hand, not only does it let us completely shit on pult, but it's also a very strong supportive option that I think will definitely secure ourselves a spot on teams. On the other hand, going with this ability does have a pretty big downside in that we aren't really going to be able to spread Paralysis as well as we would want with our typing. However, I personally think that the pros here outweigh the cons, and I think that this would be a very cool option to pursue, especially in a metagame where there's so much status spreading and few ways to really deal with it for a lot of teams.
Water Bubble: I'm very concerned about the strength of this ability, and I think that unless we gimp ourselves offensively during the stats stage (Which is admittedly a route we can go down, but is not one that we like), then it's fairly likely that going with this ability is just going to turn us into a breaker, as our typing synergizes extraordinarily well with Water-type coverage (Which we can't exactly not give this thing, considering that Tera Blast is a move), and the boost Water Bubble gives to said coverage is insanely strong.
Grass Pelt: Quite frankly, this ability is useless on CAP35. Grassy Terrain teams are very much struggling in CAP (Rillaboom has an 18.75% win rate in CAPPL, which is abysmal), and even if we were to look past this, we're not really going to be fitting that well on a hyper offense playstyle when our job here is to be a wall. It doesn't help that many of the things that we would try to cover on these types of teams are already dealt with by mons that are run fairly often on these types of teams.
Misty Surge: This ability is a pretty big a double-edged sword. On one hand, not only does it let us completely shit on pult, but it's also a very strong supportive option that I think will definitely secure ourselves a spot on teams. On the other hand, going with this ability does have a pretty big downside in that we aren't really going to be able to spread Paralysis as well as we would want with our typing. However, I personally think that the pros here outweigh the cons, and I think that this would be a very cool option to pursue, especially in a metagame where there's so much status spreading and few ways to really deal with it for a lot of teams.
Water Bubble: I'm very concerned about the strength of this ability, and I think that unless we gimp ourselves offensively during the stats stage (Which is admittedly a route we can go down, but is not one that we like), then it's fairly likely that going with this ability is just going to turn us into a breaker, as our typing synergizes extraordinarily well with Water-type coverage (Which we can't exactly not give this thing, considering that Tera Blast is a move), and the boost Water Bubble gives to said coverage is insanely strong.
Grass Pelt: Quite frankly, this ability is useless on CAP35. Grassy Terrain teams are very much struggling in CAP (Rillaboom has an 18.75% win rate in CAPPL, which is abysmal), and even if we were to look past this, we're not really going to be fitting that well on a hyper offense playstyle when our job here is to be a wall. It doesn't help that many of the things that we would try to cover on these types of teams are already dealt with by mons that are run fairly often on these types of teams.