In the last generation, Kabutops was known as one of the most fearsome OU rain sweepers, with its impressive base 115 Attack stat and base 80 Speed doubled by Swift Swim. Its Water- and Rock-type STAB attacks are resisted by very few Pokemon. Those who do resist it, such as Empoleon or Ferrothorn, are destroyed by Low Kick. Kabutops can also easily take advantage of other Drizzle teams, so you do not have to worry about keeping the rain up manually.
Kabutops does have its downfalls, though. It greatly suffers from the dreaded four moveslot syndrome, and no matter what moves it chooses, there will always be a counter to Kabutops. Rain must also be generated via Rain Dance, due to the fact that the Drizzle + Swift Swim combo has been banned, which can be hard. Despite this, Kabutops is an excellent Pokemon and should be considered when creating a rain team.
Kabutops can easily double its already impressive base 115 Attack with a single Swords Dance. In conjunction with Swift Swim's Speed boost, this makes Kabutops immensely difficult to counter. Waterfall becomes insanely powerful in the rain, having a Base Power of 180. It also has a nifty (though small) chance of flinching the foe, which is great if the opponent somehow survives Waterfall. Stone Edge is its secondary STAB attack, and hurts any cheeky Grass-, Dragon-, or Water-type Pokemon trying to switch in. The last moveslot depends on which Pokemon your team has trouble with. Aqua Jet should be the primary move, because it can hit priority users before they hit back with Mach Punch or Bullet Punch. However, Low Kick does severe damage to Empoleon and Ferrothorn, two Pokemon which rain teams have difficulty countering.Team Options & Additional Comments >>>
One problem that Kabutops faces is setting up. Slapping a Choice Band on it can cure this problem, and enables it to act as a late-game cleaner. With a Choice Band, rain-boosted Waterfall still does considerable damage to anything that does not resist it. Stone Edge is ideal for hitting bulky Water-types. With Stealth Rock and an Adamant nature, it can OHKO 156 HP / 96 Def Gyarados (the standard bulky Gyarados spread) even at -1 Attack, and has a chance of 2HKOing 252 HP / 252 Def Bold Suicune. Aqua Jet prevents other priority users from ruining Kabutops's day. Superpower is recommended in the final moveslot, as it can dismantle Ferrothorn and Empoleon. Superpower will also deal more damage to Breloom and Virizion than any of Kabutops's other attacks.Team Options & Additional Comments >>>
Like almost every other Water-type Pokemon in this generation, Kabutops learns Scald. However, its pitiful Special Attack stat prevents it from using the move. Kabutops can run a set with Endure / Flail / Aqua Jet, but it has better things to do. Besides, with priority being thrown everywhere, that set would become nothing but a gimmick. Defensive sets can opt to use Confuse Ray for fun, but relying on luck is generally not advisable. Rapid Spin is an option, although Starmie, Forretress, and Tentacruel are probably better options for spinning away entry hazards. Kabutops can set up rain itself, but there are other Pokemon who can do this more easily.
Checks and Counters
First of all, removing the rain suddenly makes Kabutops slower and weaker. Ninetales, Tyranitar, and Abomasnow can change the weather with their abilities, and all three can carry moves which are super effective. However, Kabutops also learns moves which can badly damage them (especially after a Swords Dance), so they must switch in carefully. Sun teams in particular are dangerous, because they can easily bring down an entire rain team if unaccounted for.
Kabutops does not like status at all. Tentacruel resists everything except for Stone Edge, and can lay down Toxic Spikes to shorten its life, or burn it with Scald. Will-O-Wisp from Jellicent or Thunder Wave from Celebi also ruin its day. Whimsicott deserves a special mention here, because it can cripple Kabutops with Stun Spore or Encore, and has priority while doing so.
Bulky Grass-types, such as Ferrothorn and Celebi, can shrug off a +2 Stone Edge and OHKO Kabutops with their powerful Grass-type moves. If not running Superpower / Low Kick, Empoleon, Virizion, and Breloom can wall Kabutops to no end. If Kabutops does not have Aqua Jet, Breloom and Conkeldurr can use Mach Punch to hurt it before it has the chance to attack. Finally, any Swift Swim Kabutops running an Adamant nature is in danger of being outsped by Choice Scarf Starmie, Mienshao, Gengar, and other threats.