Moves
Shell Smash makes Shellder super threatening, doubling both its Speed and its Attack. Icicle Spear and Rock Blast benefit from Skill Link, changing them from subpar attacks into Shellder's best offensive moves. Multi-hit attacks have some weird mechanics in LC, causing them to hit especially hard and be stronger than any of Shellder's STAB attacks. Moreover, Ice and Rock coverage is overall excellent, missing only Steel-types. Between just these two attacks, Shellder is truly an offensive threat and among the best sweepers in the tier. Liquidation is used to OHKO Mudbray and most Steel-types easily. Ice Shard can be run instead, primarily to KO Doduo and Diglett before they can use their strong priority options to revenge kill a weakened Shellder; however, Liquidation is generally better, as it makes Shellder far harder to wall.
Set Details
Skill Link is what makes Shellder so deadly, guaranteeing its multi-hit moves always hit five times, thus dealing the most possible damage. In LC, multi-hit moves are even more powerful than their Base Power would indicate thanks to the intricacies of the damage formula, giving Shellder amazing power. Shellder opts for an Impish nature over an Adamant one in favor of increasing its Defense to improve its survivability and setup capabilities, which are further bolstered by an Eviolite. The Attack investment without a boosting nature is more than adequate anyway, as +2 Icicle Spear and Rock Blast have the same damage rolls as they would with an Adamant nature. The Speed investment allows +2 Impish Shellder to outspeed 17 Speed Choice Scarf Pokemon such as Choice Scarf Mienfoo. A Jolly nature is also viable to allow Shellder to outspeed Scarf Doduo and Gastly after Shell Smash. The remaining EVs are invested into HP to give Shellder slightly better bulk.
Usage Tips
As with any sweeper, Shellder's checks need to be weakened before it can sweep. Some troubling Pokemon need to be scouted for, such as Chinchou and Tirtouga, as Berry Juice variants check Shellder while other variants do not. Otherwise, using Shellder is rather straightforward: set up on a physical attacker, avoid setting up on a status user, and proceed to sweep.
Team Options
Memento users, especially Cottonee and Diglett, pair well with Shellder, often giving it amazing setup chances and helping to keep it healthy enough to avoid being revenge killed. Diglett is also able to trap and weaken troubling Pokemon such as Chinchou and potentially Pawniard, while Cottonee is able to provide more utility through Knock Off support and act as a defensive pivot. Knock Off users are pretty good Pokemon to pair with Shellder too, as they remove Eviolites from the bulkiest Pokemon in the tier, allowing Shellder to blast through them. Vullaby is a great Knock Off user and is excellent at breaking down a number of checks it has in common with Shellder. Mienfoo and Timburr also pair well with Shellder, as they use Knock Off to remove Eviolites from some troubling Pokemon. More importantly, both are able to lure and exploit Croagunk and Snubbull, potentially removing one to make Shellder's sweep easier. Magnet Pull Magnemite is a decent partner that allows Shellder to drop Liquidation and run Ice Shard to prevent being revenge killed. Abra with Knock Off and Shadow Ball is a good wallbreaker for Shellder, as the set lures and beats Slowpoke and Honedge, two of the better, though uncommon, counters to Shellder. Lastly, Stealth Rock support is a necessity, making most reliable Stealth Rock users a good pairing. Hippopotas, Onix, and Pawniard are particularly good teammates due to helping fend off Electric-types and being the most reliable Stealth Rock users available.
