Punchshroom
FISHIOUS REND MEGA SHARPEDO
There's no denying that Rain is a very powerful playstyle and it is devastating if used well, however I still don't think Damp Rock warrants a ban.
* For one, it will heavily neuter Rain to the point where no one would give it a look. A fine example of this is Trick Room, where despite the presence of powerhouses like Marowak, Octillery and Rampardos, they just can't sweep opponents long enough to be considered a remote threat in most cases. Currently, Trick Room is best used if the Trick Room setter itself is going for the sweep, like Beheeyem or Duosion. Without Damp Rock, Rain would hardly see much success, limiting itself to the likes of Ludicolo or Swanna as Rain setters looking to support themselves instead of others as well.
* Secondly, you claim that it throws much of the opponent's strategies out the window, however this is merely an indication of how Rain takes advantage of today's metagame's more offensive and frailer playstyle, as most of them can't deal with the speed and power increase, much like the case of Sun. After all, there wasn't much talk about 8 turns of Rain swamping many teams during the era where the likes of Gardevoir, Braviary and Musharna were more popular than they are today. If anything, this could be the kind of push we need to bring defensive teams back into the spotlight (You mentioned that Alomomola, Mantine and Munchlax could be problems). Since the RU drops in Scolipede, Jynx and Primeape have shaken up the tier to adopt more offensive playstyles, if Rain (and by extension Sun, I can't stress this enough) can put these offensive teams in their place this could balance out NU by giving defensive teams their chance to shine once more.
Edit: You still haven't fixed that Toxic Spikes weakness I see. This is what I mean by Rain teams being devastatingly weak to them, since they have almost no room for a Poison-type on their team since Amoonguss's departure (:[) , so that's an easy strategy defensive teams (or lead Scolipede) can pull off on you.
* For one, it will heavily neuter Rain to the point where no one would give it a look. A fine example of this is Trick Room, where despite the presence of powerhouses like Marowak, Octillery and Rampardos, they just can't sweep opponents long enough to be considered a remote threat in most cases. Currently, Trick Room is best used if the Trick Room setter itself is going for the sweep, like Beheeyem or Duosion. Without Damp Rock, Rain would hardly see much success, limiting itself to the likes of Ludicolo or Swanna as Rain setters looking to support themselves instead of others as well.
* Secondly, you claim that it throws much of the opponent's strategies out the window, however this is merely an indication of how Rain takes advantage of today's metagame's more offensive and frailer playstyle, as most of them can't deal with the speed and power increase, much like the case of Sun. After all, there wasn't much talk about 8 turns of Rain swamping many teams during the era where the likes of Gardevoir, Braviary and Musharna were more popular than they are today. If anything, this could be the kind of push we need to bring defensive teams back into the spotlight (You mentioned that Alomomola, Mantine and Munchlax could be problems). Since the RU drops in Scolipede, Jynx and Primeape have shaken up the tier to adopt more offensive playstyles, if Rain (and by extension Sun, I can't stress this enough) can put these offensive teams in their place this could balance out NU by giving defensive teams their chance to shine once more.
Edit: You still haven't fixed that Toxic Spikes weakness I see. This is what I mean by Rain teams being devastatingly weak to them, since they have almost no room for a Poison-type on their team since Amoonguss's departure (:[) , so that's an easy strategy defensive teams (or lead Scolipede) can pull off on you.