Getting back to the CCAT, Here are my suggestions for our final three Pokemon
Sableye @ Leftovers
Ability: Prankster
EVs: 248 HP / 252 SDef / 8 Def
Careful Nature
- Knock Off
- Taunt
- Recover
- Will-O-Wisp
Sableye not only gives our team a spinblocker, but can also prevent Defog through smart switching and Prankster Taunt. Priority Will-o-wisp allows Sableye to neutralize most physical attackers, while Recover is its needed recovery. In addition, Sableye has pretty good synergy with Aggron and Florges, resisting the Fighting and Poison-type moves that hit them respectively. Finally, Sableye helps prevent our team from being swept by Crcune (Suicune with CM, Scald, Rest, Sleep Talk).
Starmie @ Leftovers
Ability: Natural Cure
EVs: 248 HP / 60 Def / 200 Spe
Timid Nature
- Scald
- Rapid Spin
- Recover
- Ice Beam / Psyshock
Starmie allows us to clear hazards away from our side of the field without removing the hazards that we set. In addition, its high speed allows it to be an emergency check to Pokemon like CB Darmanitan in case Mega-Aggron and Rotom-H are weakened. Scald is STAB, while Ice Beam or Psyshock gives Starmie good coverage. The given EVs maximize Starmie's bulk while allowing it to outspeed base 108s.
Chesnaught @ Rocky Helmet
Ability: Bulletproof
EVs: 248 HP / 252 Def / 4 Spe
Impish Nature
- Spikes
- Synthesis
- Hammer Arm
- Roar / Leech Seed / Spiky Shield
Chesnaught completes a Fire-Water-Grass core, while providing important Water, Ground, and Rock, and Dark-type resistances. It's great physical bulk allows it to check common physical attackers such as Sharpedo, while being able tank U-turns with ease. Spikes gives us entry hazards, Synthesis is for recovery, Hammer Arm is STAB. The last slot is can be changed as we test the team - Roar, Leech Seed, and Spiky Shield are all good options.