Excadrill serves two main roles in the Uber tier. Firstly, with a high base 135 Attack and an ability that doubles its decent base 88 Speed in sandstorm, Excadrill is a terrifying sweeper. Swords Dance is the icing on the cake, pumping Excadrill's already high Attack stat to insane levels. Excadrill has the perfect typing for a sweeper too, being immune to both Thunder Wave and Toxic, while resisting Stealth Rock. Its concise movepool contains all it needs to sweep, allowing it to act as a decent offensive Rapid Spin user. Secondly, Excadrill possesses the bulk and typing to run a bulky spinner set in the rain. Its ability, Mold Breaker, allows it to smash the commonly used spinblocker, Giratina-O, with a powerful STAB Earthquake.
I know you're thinking that this is probably an April Fool's joke or something of that sort, but it isn't. Bulky Excadrill is quite the viable Pokemon in Ubers, and most players will agree that it is quite a bit more useful than its more offensive counterpart. Although Excadrill might seem terribly unsuited to the role of a bulky spinner, it has some extremely subtle advantages that help it perform well in this role. First of all is its incredible typing, which gives it an immunity to both Toxic and Thunder Wave, as well as a lovely Dragon-type resistance. In a metagame where Dragon-types are everywhere, this can be incredibly useful. Apart from that, Excadrill is surprisingly bulky and, though its Defense might seem lackluster, its invested special bulk is greater than that of Forretress, which is a popular spinner in Ubers. Lastly, it is an effective check to Pokemon that give most teams nightmares, such as Bulk Up Dialga, Giratina-O, Substitute + Hone Claws Zekrom, and Dark Arceus. Excadrill can also shakily check Latias and Latios without Surf or Hidden Power Fire; however, a +1 Dragon Pulse 3HKOes Excadrill without fail.
Furthermore, Excadrill is probably the only Rapid Spin user in Ubers capable of threatening stall, as few Pokemon on a standard stall team can beat it. However, Ferrothorn with Power Whip will give Excadrill trouble, as well as the omnipresent Kyogre. Groudon and certain support Arceus formes will also prove problematic for Excadrill. However, mixed Giratina-O, the most commonly used spinblocker, actually loses to Excadrill, because Hidden Power Fire will not even 3HKO Excadrill in rain, while Excadrill's boosted Earthquake can 2HKO back. Earthquake is the obligatory STAB move, hitting many threats hard off the bat. Swords Dance paired with Mold Breaker Earthquake allows Excadrill to bust through the aforementioned Giratina-O, and even leads to an occasional sweep. Rock Slide can also be used to hit Ho-Oh, Rayquaza, and Shaymin-S on the switch-in. Substitute with mono-type coverage is actually viable due to Mold Breaker, and should be considered if Excadrill's only goal is to spin; Substitute eases prediction, blocks Leech Seed and Will-O-Wisp, and prevents Dragon Tail Giratina from phazing Excadrill out.Team Options & Additional Comments >>>
After a Swords Dance, Excadrill reaches a mammoth 738 Attack with a Jolly nature, or 810 with Adamant. Thanks to its excellent ability, Excadrill's Speed doubles in sandstorm, allowing it to outspeed every non-Choice Scarf user in the game. If using a Jolly nature, Excadrill hits 604 Speed, while with Adamant, it sits at an impressive 550 Speed, still enough to outspeed Deoxys-S, the fastest unboosted Pokemon in the game.
A +2 STAB Earthquake will dent anything not resisting it, and even support Groudon takes a hefty 61.6% - 72.8% from Jolly Excadrill, a sure 2HKO. Rock Slide hits all Pokemon resistant to Ground-type moves, with the notable exception of Bronzong. The last move is mainly filler and depends on what Excadrill wants to hit. Iron Head is the primary option, as it can OHKO Giratina-O at +2 if it does not invest in bulk, and it also provides a strong neutral move to use against Gliscor and Grass Arceus. Rapid Spin can also go in the last slot as Excadrill makes a fantastic offensive Rapid Spin user, its Steel typing giving it a natural immunity to Toxic Spikes and a resistance to Stealth Rock, and Air Balloon granting it immunity to Spikes. Shadow Claw can be used if bulky Giratina-O is a concern, but even when boosted it can only get the KO on those that only invest in HP, not Defense.Team Options & Additional Comments >>>
Excadrill has a rather shallow movepool, so it doesn't have many viable options outside of the ones mentioned. X-Scissor can be used over Shadow Claw to get a harder hit on Psychic-types and Grass Arceus, but Excadrill loses precious coverage against Giratina-O. Toxic can also be used to cripple walls such as Lugia that laugh at most of Excadrill's moves.
Checks and Counters
Skarmory is the best defensive response to Excadrill, as it is immune to Earthquake and resists Excadrill's other STAB. It can then Roost off the damage if required or even phaze out Excadrill with Whirlwind. However, Skarmory can't hurt Excadrill back and has a good chance to be 2HKOed by a boosted Rock Slide after Stealth Rock. Bronzong resists or is immune to all of Excadrill's moves, and with an Earthquake of its own can check it easily. Bold Lugia can check Excadrill provided Stealth Rock is off the field. Giratina can just burn Excadrill and phaze it out, but loses if Excadrill gets a flinch from a boosted Iron Head, as it will then be KOd by Earthquake the next turn. Gliscor can check the mole thanks to Poison Heal, excellent physical bulk, and an immunity to Earthquake; however, it falls to a +2 Iron Head.
Offensive Kyogre and Groudon can switch in and remove the sandstorm from play, negating Excadrill's Sand Rush ability. With enough investment in Speed, they can then proceed to destroy Excadrill with Surf or Earthquake, respectively. Rayquaza ignores Sand Rush thanks to Air Lock, and can OHKO Excadrill with Fire Blast or Earthquake. Grass Arceus can survive a boosted Earthquake, and do 59-70% to Excadrill with Judgment or cripple it with Will-O-Wisp, but will lose if it gets flinched by Iron Head. Defensive Normal Arceus, though rare, survives any attack from Excadrill, and can neuter it with Will-O-Wisp. Landorus-T is immune to Earthquake and has Intimidate; however, it still takes heavy damage from a +1 Iron Head. An opposing Excadrill with Air Balloon or a faster spread can revenge kill Excadrill with an Earthquake of its own, but +2 Iron Head still does a lot of damage, despite being resisted. Air Balloon Terrakion can set up a Rock Polish on Excadrill if it is not using Iron Head, and then outspeed and KO it the next turn. Choice Scarf Ditto can revenge Excadrill without Air Balloon; however, a Choice-locked Earthquake is very easy to predict and take advantage of.