What it does
Weather Ball is a special move whose type and power are weather-dependent. No weather: Normal-type, low base power — essentially unused. Active weather: power doubles, and the move's type becomes the matching weather type. Sun → Fire, Rain → Water, Sand → Rock, Hail → Ice. Shadow Sky reads as no weather for this move.
The doubled power is what makes it competitive. In sun, Torkoal with Drought fires a Fire-type Weather Ball that also gets the sun 50% damage boost and STAB — the combination stacks damage multipliers fast. In rain, Water-type users like Pelipper or Politoed get STAB on top of the rain Water boost. The move isn't just 'weather-themed flavor'; it's a legitimately high-output attack in the right conditions.
100% accuracy. No secondary effects. Just a big hit in the right weather.
Single-target in doubles — full damage on one Pokémon, no spread reduction.
Who runs it
Pelipper at 87% sets rain with Drizzle on switch-in and immediately threatens Water-type Weather Ball with STAB. Its setup and attack role overlap cleanly.
Politoed at 83% is the same archetype — Drizzle, then Water STAB Weather Ball for offense alongside its support role.
Torkoal at 52% sets sun with Drought and fires Fire-type Weather Ball into sun's damage multiplier. Combined STAB + sun boost makes this one of the hardest-hitting Fire attacks in the game under those conditions.
Castform at 69% has STAB on Weather Ball in every weather condition because its type changes to match the weather. It's the only Pokémon that naturally maintains STAB on Weather Ball across all weather types — switching the weather type doesn't remove its STAB, it just changes it.
Charizard at 58% runs it in sun teams. Fire STAB in sun is the same damage profile as Torkoal's.
Heliolisk at 26% benefits from rain through Dry Skin — Water immunity plus HP recovery, and then a Water-type Weather Ball to add offensive pressure.
How to use it
Verify weather is active before clicking Weather Ball. Neutral weather makes it a dead move slot — never click it out of weather.
In doubles, having your weather setter and your Weather Ball user in the field simultaneously is ideal. One Pokémon maintains the condition, the other fires into it. Opponents face a compound problem: handle the weather or handle the attack — often they can't cleanly do both in one turn.
Track weather changes in real time. Opposing weather setters can override your weather mid-battle, flipping Weather Ball's type. This can work in your favor (their sun suddenly makes your Weather Ball Fire-type against a Grass target) or against you (you expected Water, got Rock). Read the board.
Tips & strategy
When your weather timer runs out, Weather Ball immediately reverts to weak Normal-type. Managing weather duration is a core skill in weather-based teams — get the hits in before the timer expires.
Castform's type-tracking STAB is genuinely hard to exploit. Opponents who try to counter it by shifting weather find its STAB just changes type instead of disappearing. That resilience is part of why it sees play on Weather Ball sets.