What it does
Water Shuriken is a +1 priority Water-type special move, 15 base power per hit, landing 2–5 times. The priority means it fires before most regular moves — only moves with +2 priority or higher cut ahead of it.
Each hit resolves individually. That matters for a few reasons. If your target has Sturdy or is holding a Focus Sash, the first hit drops them to 1 HP and the follow-up hits KO. Each hit also triggers on-hit ability effects separately — Weak Armor would drop Defense and raise Speed once per hit, not once total. The flip side: you might hit only twice (30 total BP) or all five times (75 total BP), and that variance is real.
Expected hits average exactly 3 per use, putting average total power at 45. For a priority move, that is competitive — most priority options are 40 BP or lower at a single hit.
Water hits Rock and Ground types for 2×, which is solid coverage.
Who runs it
Greninja at 12% usage. Greninja is already one of the fastest non-Scarfed Pokémon in the format, so it does not need priority against most opponents. Water Shuriken is the insurance policy — when someone is running a Choice Scarf or just has higher raw Speed, this move lets Greninja still go first.
How to use it
The main application is threatening targets that would otherwise outspeed Greninja. On anything slower, Greninja does not need the priority and can use a higher-power Water move. On anything faster, Water Shuriken forces the issue.
Sash-breaking is the second major use. When an opponent is holding a Focus Sash, one strong hit leaves them at 1 HP — they survive. Water Shuriken hits once, trips the Sash, then the second hit KOs through it. This is one of the few priority moves that reliably punches through Focus Sash in a single turn.
Torrent kicks in when Greninja drops below a third of its HP. Every individual hit of Water Shuriken gets the Torrent boost during that window, so the move becomes noticeably stronger the closer to death Greninja gets.
Tips & strategy
Do not treat Water Shuriken as a guaranteed KO tool. Two hits versus five hits is a wide range, and building a game plan that requires the five-hit outcome to work is asking for trouble. Use it to chip, to clean up low-HP targets, or to break Sashes — not to nuke a full-HP Pokémon from range.
One thing that trips people up: Water Shuriken is a special move despite looking like a thrown physical projectile. EV investments and nature choices for Greninja should reflect that — special attack investment is what makes this move stronger.
In doubles, the +1 priority matters even on turns when your partner gets hit by Fake Out. Your partner loses their action, but Greninja can still fire Water Shuriken before the opposing Pokémon moves, keeping some pressure on the field during what would otherwise be a completely free turn for your opponent.