Slowbro

Amnesia Slowbro has gone down in history as one of the most famous and well-known sets in the world of competitive Pokemon. Generally known as TobyBro, Amnesia Slowbro is a moveset that combines both simplicity and efficiency. The RBY version of Amnesia is arguably the best stat-boosting move of all time, raising the Special stat by two stages. It quickly powers up Slowbro's Special moves, while covering its main defensive weakness: Electric-type attacks. Having one of the best physical defense stats in the game and learning Thunder Wave to make up for its awful Speed greatly helps make Slowbro more threatening as well.

However, Slowbro is also a bit of an all-or-nothing Pokemon and requires some luck, which are the main reasons why it's often an overlooked Pokemon. Without setting up, Slowbro is basically a useless Pokemon; it can't Recover to work as a wall for a long time, and offensively, it lacks Explosion or a sleep move, unlike other specially based Pokemon. On the other hand, if Slowbro sets up, it's meant never to switch out, so the user is inevitably taking some risks; Electric-type moves fail to get past a +6 Slowbro normally, but with a critical hit, a non-STAB Thunderbolt will nearly OHKO Slowbro while a STAB Thunderbolt will OHKO outright. With critical hit rates being much higher in RBY than in later generations, it's not really "bad luck" when Slowbro ultimately ends up falling to a critical hit Thunderbolt. To a lesser extent, this can also be applied to the physical side, potentially turning 4HKOs into 3HKOs, letting a physical sweeper get past Rest. However, while it's true that Slowbro depends on quite a bit on luck, it also requires a good deal of skill, and Slowbro can be one of the most dangerous Pokemon in the first generation, being the best Amnesia user in RBY after Mewtwo.