A Water-type (excluding Magikarp) without Ice Beam? Those exist?
Seismitoad @ Choice Specs
Trait: Water Absorb / Swift Swim
EVs: 32 HP, 252 SpA, 224 Spd
Modest Nature
-Hydro Pump
-Earth Power
-Sludge Wave / Grass Knot
-Hidden Power [Ice]
With Seismitoad's good typing and bulk, it makes for a decent all-out attacker, and the extra immediate power can really help Seismitoad take down certain counters, such as Vileplume and Altaria. Hydro Pump is Toad's strongest STAB, and is the move you're gonna be spamming most often. Earth Power is his best Ground STAB, and it comes with the advantage of being a solid 2HKO on 252/0 Vileplume. Sludge Wave is the primary coverage move, hitting most mono-Grasses for a ton of damage. However, Grass Knot can hit bulky Waters such as Alomomola and opposing Toads, so that can be used instead. Finally, HP Ice (because again, HE CAN'T LEARN ICE BEAM -__-) can easily 2HKO any variant of Altaria, and OHKOes after SR.
EV spread is the same as Raseri's, for the same purposes. Water Absorb is the main ability because it lets Toad switch in much more often, but Swift Swim can be used to make him a decent check for Ludicolo in rain (Sludge Wave does 84%+ to it). However, this is pretty situational, and Seismitoad can't switch in on Ludi's Giga Drain, anyway. Therefore, Water Absorb is usually better.