Clavavera @ Focus Sash
Ability: Beat Hereafter
Nature: Jolly (+Spe, -SpA)
252 Atk/252 Def/4 SpA, 252 Atk/4 Def/252 Spe, 252 SpA/252 SpD/4 SpA, or 252 SpA/4 SpD/252 Spe
- Stealth Rock/Spikes
- Parting Shot
- Protect/Life Dew/Aqua Ring/Strength Sap/Synthesis
- Will-O-Wisp/Perish Song/Leech Seed/Aromatherapy/Taunt/Encore/Disable/Poltergeist/Last Respects/Shadow Ball/Earth Power/Earthquake/Scorching Sands
Your bog-standard all-purpose hazard-setter/pivot set, with some offensive potential on the side. Whichever stats you pick for topping off EVs is dependent on whether you want her to be fast enough to put up
Stealth Rock (or at least one layer of
Spikes) or tough enough to take a licking while she makes her rounds, especially with a
Focus Sash to give her a crucial extra turn.
Parting Shot is essential for pivoting, but faster opponents may warrant running
Protect alongside it to buy her additional time in case her Focus Sash is already broken; alternatively,
Life Dew, Aqua Ring, Strength Sap, and
Synthesis all offer a welcome if often small sip of recovery (the latter being especially useful for sun teams) in case she has to escape a fight she can't win. She has many other ways to support her team, too:
Will-O-Wisp, Perish Song and
Leech Seed all put walls on a timer (with the former also deterring physical attackers with the debuff of its burn),
Aromatherapy helps keep status off her and her teammates' backs, and
Taunt, Encore, and
Disable can shut down enemy stallers. In case she gets Taunted herself, though, she can always run any one of her STAB options instead since many of them have utility effects of their own.
Clavavera @ Leftovers, Ability Shield, or Weakness Policy
Ability: Beat Hereafter
Nature: Adamant (+Atk, -SpA), Modest (+SpA, -Atk), Timid (+Spe, -Atk), or Jolly (+Spe, -SpA)
252 Atk/252 Def/4 SpA, 252 Atk/4 Def/252 Spe, 252 SpA/252 SpD/4 SpA, or 252 SpA/4 SpD/252 Spe
- Poltergeist/Last Respects/Shadow Ball
- Earth Power/Earthquake/Scorching Sands
- Accelerock/Chilling Water/Energy Ball/Future Sight/Leaf Storm/Petal Dance/Rock Slide/Seed Bomb/Stone Edge/Trailblaze
- Swords Dance/Calm Mind
With optimal EV investment and the right opportunity, Clavavera will have no trouble taking on her opponents in direct combat, especially during the late game, thanks to her deceptive combination of balanced bulk and an unconventional Speed buff. Her choice of held item for her offensive set would depend on what risks you think she might encounter:
Leftovers helps with her staying power for drawn-out fights, an
Ability Shield will ensure that the
Beat Hereafter will continue irrespective of foes with Mold Breaker, and a
Weakness Policy enables her to set up without wasting a turn if hit by a super-effective attack, which can come in handy should her chosen target happen to be running a coverage move just to deal with her. Depending on her chosen nature, EVs, and held items, her STABs of choice can be either physical, special, or even a mix of both to mess with her opponents' heads, and their being resisted by only five type combos is not nothing by any stretch, but her coverage is better for broadening her range of super-effective hits than checking things that can hit her super-effectively in turn. Still, with enough advance planning and a bit of luck, you could get a lot of mileage out of her as a balanced cleaner who can work equally well with either
Swords Dance or
Calm Mind.