Kingler

With a cataclysmic Attack stat that can be boosted by Swords Dance, Kingler can function as a serviceable late-game sweeper that bullies paralyzed Pokemon. With the exclusive STAB Crabhammer, its mediocre Special is largely made up for and gives it unresisted coverage, meaning Kingler is capable of dealing with common obstacles to its sweep such as Rhydon and Gengar. Furthermore, Kingler's Speed is just high enough to pose an offensive threat, being faster than defensive presences like Cloyster, Chansey, and Snorlax. Thus, stopping Kingler from steamrolling or breaking holes in a team can be quite difficult if the stage is set.

However, Kingler is only barely viable in Stadium OU. Hyper Beam is massively nerfed in Stadium, so its offensive capabilities are noticeably worse. Furthermore, its low Special and middling Speed mean that any strong special attacker like Alakazam or Starmie can 2HKO and revenge kill it with ease; this also makes it very difficult to switch in. A somewhat related weakness is that Kingler's frailty and Speed reliance mean it cannot afford to be paralyzed at all. Its weakness to the abundant Thunderbolt only worsens this; many users can outright OHKO it. Kingler is monumentally reliant on paralysis support, which is very hard to provide. Due to these factors, finding opportunities for Kingler to succeed is very difficult; ergo, it is generally not recommended on conventional teams.