All this talk about water spam reminded me about a set I've been using lately that I think will work nicely in this new meta. I used to run it while Poli was still around as a way to check both S ranks but I think it still serves the purpose:
Gogoat @ Assault Vest
Ability: Sap Sipper
EVs: 252 Atk / 180 SpD / 76 Spe
Adamant Nature
- Horn Leech
- Zen Headbutt
- Earthquake
- Rock Slide
AV Gogoat is a great check to most special attackers in the tier, not only because it is able to retaliate with an appropriate coverage move but also maintain its health high with the semi-reliable Horn Leech. Another advantage is that it is physical attacker, which is nice considering that most special attackers have low phy. defense. The speed EVs are there to better check offensive Roselia and the rest into attack and special defense to maximize damage output and bulk.
Here's a list of what it accomplishes to tank and hit back:
Offensive Roselia
252+ SpA Roselia Sludge Bomb vs. 0 HP / 180 SpD Assault Vest Gogoat: 176-210 (45.4 - 54.2%) -- 43% chance to 2HKO
252+ Atk Gogoat Zen Headbutt vs. 160 HP / 0 Def Eviolite Roselia: 200-236 (71.1 - 83.9%) -- guaranteed 2HKO
Defensive Roselia
0 SpA Roselia Sludge Bomb vs. 0 HP / 180 SpD Assault Vest Gogoat: 128-152 (33 - 39.2%) -- 99.8% chance to 3HKO
252+ Atk Gogoat Zen Headbutt vs. 252 HP / 128 Def Eviolite Roselia: 160-190 (52.6 - 62.5%) -- guaranteed 2HKO
Simipour
252 SpA Life Orb Simipour Ice Beam vs. 0 HP / 180 SpD Assault Vest Gogoat: 138-164 (35.6 - 42.3%) -- guaranteed 3HKO
252+ Atk Gogoat Horn Leech vs. 4 HP / 0 Def Simipour: 326-386 (111.6 - 132.1%) -- guaranteed OHKO
Zebstrika
252 SpA Life Orb Zebstrika Overheat vs. 0 HP / 180 SpD Assault Vest Gogoat: 174-205 (44.9 - 52.9%) -- 28.1% chance to 2HKO
252+ Atk Gogoat Earthquake vs. 0 HP / 0 Def Zebstrika: 292-344 (100.3 - 118.2%) -- guaranteed OHKO
Kadabra
252 SpA Kadabra Signal Beam vs. 0 HP / 180 SpD Assault Vest Gogoat: 102-120 (26.3 - 31%) -- guaranteed 4HKO
252+ Atk Gogoat Horn Leech vs. 4 HP / 0 Def Kadabra: 276-325 (124.3 - 146.3%) -- guaranteed OHKO
Floatzel
252 SpA Choice Specs Floatzel Ice Beam vs. 0 HP / 180 SpD Assault Vest Gogoat: 144-170 (37.2 - 43.9%) -- guaranteed 3HKO
252+ Atk Gogoat Horn Leech vs. 0 HP / 0 Def Floatzel: 362-428 (116.3 - 137.6%) -- guaranteed OHKO
Grumpig
252+ SpA Grumpig Signal Beam vs. 0 HP / 180 SpD Assault Vest Gogoat: 90-108 (23.2 - 27.9%) -- 79% chance to 4HKO
252+ Atk Gogoat Horn Leech vs. 248 HP / 0 Def Grumpig: 160-189 (44 - 52%) -- 13.3% chance to 2HKO
Regice
252 SpA Life Orb Regice Ice Beam vs. 0 HP / 180 SpD Assault Vest Gogoat: 211-250 (54.5 - 64.5%) -- guaranteed 2HKO
252+ Atk Gogoat Rock Slide vs. 0 HP / 0 Def Regice: 150-178 (49.8 - 59.1%) -- 99.6% chance to 2HKO
Mr. Mime
252 SpA Mr. Mime Psychic vs. 0 HP / 180 SpD Assault Vest Gogoat: 81-96 (20.9 - 24.8%) -- guaranteed 5HKO
252+ Atk Gogoat Horn Leech vs. 0 HP / 0 Def Mr. Mime: 160-189 (72.3 - 85.5%) -- guaranteed 2HKO
Articuno
252 SpA Articuno Hurricane vs. 0 HP / 180 SpD Assault Vest Gogoat: 188-224 (48.5 - 57.8%) -- 95.3% chance to 2HKO
252+ Atk Gogoat Rock Slide vs. 0 HP / 0 Def Articuno: 300-356 (93.4 - 110.9%) -- 56.3% chance to OHKO
Simisear
252 SpA Life Orb Simisear Fire Blast vs. 0 HP / 180 SpD Assault Vest Gogoat: 250-296 (64.5 - 76.4%) -- guaranteed 2HKO
252+ Atk Gogoat Earthquake vs. 0 HP / 0 Def Simisear: 292-344 (100.3 - 118.2%) -- guaranteed OHKO
Pair it with something that can take physical hits e.g. Piloswine, Carracosta (and optionally with heal bell support to sustain its longevity) and you're good to go :)