What it does
Energy Ball is a special Grass-type move with 90 base power, 100% accuracy, and a 10% chance to lower the target's Special Defense by one stage. Single target. The 100% accuracy is the feature that matters most here — this move doesn't ask you to gamble on connecting.
The Sp. Def drop is a minor perk. At 10%, it happens roughly once every ten uses in expectation — not a percentage you can build around. The decision to slot Energy Ball into a moveset comes down to three factors: you need Grass-type coverage, you're a special attacker, and you need a move that reliably connects. Energy Ball fulfills all three without conditions.
Grass coverage in competitive doubles primarily targets Water, Rock, and Ground types. Gastrodon, Swampert, Rhyperior, Politoed — these are the common targets. A special attacker that lacks a Grass move is stuck doing neutral damage to these Pokémon, which is a serious coverage gap when they show up on opposing teams.
In doubles, Energy Ball as a single-target move is preferable when you need concentrated fire on a specific target rather than hitting both sides. When a teammate is adjacent and a spread move would hit them too, or when you need to cleanly remove one Pokémon without splitting power, single-target Grass is the right call.
Who runs it
Venusaur (37%) runs Energy Ball as Grass STAB. It's the most accurate Grass special move, and on a Grass-type attacker, STAB makes it the default. Under Sun with Chlorophyll, Venusaur is acting first against almost everything — Energy Ball into a Water or Ground target ends the threat quickly.
Hydrapple (33%) uses Energy Ball as primary Grass STAB. Grass/Dragon typing means this is a core move for the Sp. Atk damage output, not a coverage option. 100% accuracy STAB on a special attacker is exactly what Hydrapple wants.
Roserade (25%) is another Grass-type running it as STAB. Roserade has high Special Attack, so Energy Ball actually hits hard instead of just filling a coverage slot.
Castform (24%) runs Energy Ball for coverage rather than STAB, particularly to handle Water-type counters in certain weather conditions. It's situational, but the coverage gap it closes is real.
Abomasnow (23%) is Grass/Ice and uses Energy Ball as reliable Grass STAB to complement its Ice moves. The two types together create wide coverage, and Energy Ball's accuracy makes it the stable Grass option in the set.
Chandelure (14%) is Fire/Ghost, so Energy Ball here is pure coverage — no STAB. Against the Water and Ground types that would otherwise wall Chandelure's Fire moves, a 90-power 100% accurate coverage option is valuable even without the type bonus. It doesn't need STAB to be effective at punishing the right targets.
Reuniclus (11%) is a Psychic-type that sometimes needs Grass coverage to threaten Dark and Water types that would otherwise be annoying matchups. 11% usage reflects this as a niche rather than a default pick.
Scovillain (10%) is Grass/Fire with Energy Ball as Grass STAB. Lower usage suggests many builds prefer other options, but for pure STAB consistency, Energy Ball is correct.
How to use it
Energy Ball usage falls into two main situations: proactively KOing a known Grass-weak target (Gastrodon, Politoed, Rhyperior, Ground-types generally), or punishing when an opponent switches in a non-Grass-resistant Pokémon and you have a free hit with a reliable move.
With Choice Specs, Energy Ball's effective power reaches 135 (90 × 1.5) — enough to seriously threaten or remove most Water-type Pokémon that don't pack Grass resistance. If you're locked into Energy Ball with Specs and the opponent has a clean answer for it, the locked move penalty hurts — so the team preview read on whether your target is actually in range matters.
Read the opponent's team during team preview: if they're running Water-type or Ground-type cornerstones, your Energy Ball user becomes a priority pivot for those matchups. Know which turns you plan to bring it in, and protect that window by not wasting it on a Grass-resistant switch-in.
Tips & strategy
The 10% Sp. Def drop is worth one mention: against high Sp. Def tanks like Blissey or Cresselia, a single trigger meaningfully improves subsequent hit damage. It's not reliable enough to plan around, but if it fires, use that window before the target switches out and resets.
Miracle Seed boosts Grass moves by 20% without locking the move choice. It's strictly weaker per-hit than Choice Specs, but the flexibility of using other moves in the set is worth the tradeoff for some builds. If your Grass-type attacker needs to run multiple coverage moves, Miracle Seed keeps Energy Ball competitive without the Specs lock.
Don't confuse Sun power with Energy Ball strength. Grass moves don't get a weather multiplier in Sun — Venusaur under Sun is fast because Chlorophyll doubles Speed, not because the energy ball hits harder. The Sun damage benefit on Venusaur comes from Solar Beam charge skipping, not Energy Ball interaction.
Grass-type users are vulnerable to Fire, Ice, Flying, Bug, and Poison coverage. Timing the switch-in for your Energy Ball user is important — come in on a predicted switch, not directly into an attacker that has a super-effective move ready. The move is reliable; don't waste it by arriving at half HP.