I'm voting ban for Diglett. My explanation is as follows:
Diglett is an amazing Pokemon in ADV LC, no one's going to argue that. The question is whether or not it is broken and/or overcentralizing in the ADV LC metagame at this point in time.
I believe that Diglett should be banned for the outlined reasons:
Pros and Cons of Diggy
+Outspeeds entire meta bar Elekid and Voltorb
+Hits very hard with CB especially since it has perfect neutral coverage with EdgeQuake (SlideQuake??) and the lack of Eviolite in ADV (Proof: It can OHKO or 2HKO literally every Pokemon in ranks S through C)
+Can trap and kill checks and counters to other sweepers
+Has very few viable checks and counters
+Lack of team preview demands preservation of checks
-Frail
-Gives opponent a free turn every time it gets a KO
-Can't trap Flying types and Levitaters
Full explanation:
Diglett is overcentralizing in the current metagame. The lack of Choice Scarf in ADV means that nothing is guaranteed to outspeed DIglett, and the only two that have a chance of outspeeding it are weak to Diglett's STAB, meaning they run the risk of getting OHKOed. The metagame is also made less bulky with the lack of Eviolite, meaning that Diglett hits significantly harder than in modern ORAS LC. I've run a very large number of calcs- I've calced Diglett versus every Pokemon from S to C Rank- and Diglett hits very, very hard with a Choice Band. In fact, not accounting for Sitrus Berry, literally nothing in those ranks avoids being 2HKOed, and almost everything that avoids the OHKO can't check Diglett unless they're at full health. This is in part because of Diglett's famed EdgeQuake coverage (I suppose it's "SlideQuake" in ADV but that doesn't sound as cool), which hits every Pokemon in the tier at least neutrally. And that's not the end of end of it- no, as well as being a devastating wallbreaker in its own right, Diglett can also be paired with a sweeper like Zigzagoon to trap and eliminate its checks and counters. An argument I've seen against banning Diglett is that it's absurdly frail- it has an HP stat of 10. That's true, Diglett dies at the drop of a hat, but Pokemon can rarely hit it before it KOs them- priority is very rare in ADV, and the two Pokemon that have a chance to outspeed it are both OHKOed by Earthquake. The biggest problem with Diglett, though, is that it has few solid checks and counters, and the few Pokemon that can check it are rarely viable. This is compounded by the lack of team preview in ADV- not only are you almost forced to run a questionably viable Pokemon specifically for Diglett which often has to be at full health to reliably check Diglett- because you have to preserve a Pokemon just so you don't lose to Diglett, which forces you to play very cautiously, but in the event that your opponent doesn't have a Diglett, this check is often dead weight. This means that even in battles where Diglett is not even on either player's team, it is still influencing the playstyle of both players, as well as forcing them to run Pokemon specifically for Diglett.
As for the cons of Diglett, there are very few. Diglett is frail, but I've already covered that argument above. Probably the biggest problem with Diglett is that it gives the opponent a free turn every time it gets a KO. This is simply the opportunity cost of using Diglett, and it doesn't outweigh all of Diglett's positive traits in my eyes. It also can't trap Pokemon that are immune to Ground, but those are not very common in the metagame.
TL;DR: Diglett is just too good in this metagame. It has few viable checks and counters, and players are forced to run them so that they don't just lose to Diglett. I am voting BAN for Diglett.
Diglett Versus S through C Ranks (NOW COLOR CODED! :D)
Choice Band Diglett Earthquake vs. Diglett: 26-31 (152.9 - 182.3%) -- guaranteed OHKO
(26, 26, 26, 27, 27, 27, 28, 28, 28, 29, 29, 29, 30, 30, 30, 31)
Choice Band Diglett Earthquake vs. Elekid: 47-56 (223.8 - 266.6%) -- guaranteed OHKO
(47, 48, 48, 49, 49, 50, 50, 51, 52, 52, 53, 53, 54, 54, 55, 56) elekid has 50% chance to win, diggy has 50% chance to beat diggy lol
Choice Band Diglett Earthquake vs. Wailmer: 23-28 (76.6 - 93.3%) -- 68.8% chance to OHKO after 2 layers of Spikes
(23, 24, 24, 24, 24, 25, 25, 25, 26, 26, 26, 26, 27, 27, 27, 28) wailmer can only switch in if it's undamaged
Choice Band Diglett Earthquake vs. Horsea: 17-21 (89.4 - 110.5%) -- guaranteed OHKO after 1 layer of Spikes
(17, 18, 18, 18, 18, 18, 19, 19, 19, 19, 19, 20, 20, 20, 20, 21) aerow says 0/36 is standard spread
Choice Band Diglett Earthquake vs. Porygon: 18-22 (78.2 - 95.6%) -- 62.5% chance to OHKO after 2 layers of Spikes
(18, 18, 19, 19, 19, 19, 20, 20, 20, 20, 20, 21, 21, 21, 21, 22) not good odds
-1 Choice Band Diglett Earthquake vs. Snubbull: 15-18 (68.1 - 81.8%) -- 37.5% chance to OHKO after 3 layers of Spikes
(15, 15, 15, 15, 16, 16, 16, 16, 16, 16, 17, 17, 17, 17, 17, 18) if this thing gets weakened/diggy switches in on it, snubbull gets to die
Choice Band Diglett Earthquake vs. Voltorb: 45-54 (225 - 270%) -- guaranteed OHKO
(45, 46, 46, 47, 48, 48, 49, 49, 50, 50, 51, 51, 52, 52, 53, 54) 50% chance to win speedtie
Choice Band Diglett Earthquake vs. Chinchou: 35-42 (140 - 168%) -- guaranteed OHKO
(35, 36, 36, 36, 37, 37, 38, 38, 39, 39, 39, 40, 40, 41, 41, 42) even 76/212+ gets ohkoed
Choice Band Diglett Rock Slide vs. Pineco: 15-18 (62.5 - 75%) -- guaranteed 2HKO
(15, 15, 15, 15, 16, 16, 16, 16, 16, 16, 17, 17, 17, 17, 17, 18) maybe pineco has something to do outside of suicide lead
Choice Band Diglett Earthquake vs. Staryu: 18-22 (81.8 - 100%) -- 87.5% chance to OHKO after 2 layers of Spikes, 62.5% chance to OHKO after 1 layer of Spikes
(18, 18, 19, 19, 19, 19, 20, 20, 20, 20, 20, 21, 21, 21, 21, 22) unless it runs 196/236+ it doesn't have much of a chance
Choice Band Diglett Rock Slide vs. Doduo: 23-28 (115 - 140%) -- guaranteed OHKO
(23, 24, 24, 24, 24, 25, 25, 25, 26, 26, 26, 26, 27, 27, 27, 28) doduo really shouldn't be switching in unless diggy's locked into eq
Choice Band Diglett Earthquake vs. Ponyta: 32-38 (145.4 - 172.7%) -- guaranteed OHKO
(32, 32, 33, 33, 33, 34, 34, 34, 35, 35, 36, 36, 36, 37, 37, 38) thats with 76/236 lol
Choice Band Diglett Earthquake vs. Abra: 30-36 (157.8 - 189.4%) -- guaranteed OHKO
(30, 30, 31, 31, 32, 32, 32, 33, 33, 33, 34, 34, 34, 35, 35, 36) calcing abra for completions sake lol
Choice Band Diglett Double-Edge vs. Cacnea: 14-17 (58.3 - 70.8%) -- guaranteed 2HKO
(14, 14, 14, 14, 15, 15, 15, 15, 15, 15, 16, 16, 16, 16, 16, 17) so cac with 196/236+ actually seems to be one of the best checks lol
Choice Band Diglett Earthquake vs. Cubone: 12-15 (50 - 62.5%) -- guaranteed 2HKO
(12, 12, 13, 13, 13, 13, 13, 13, 13, 14, 14, 14, 14, 14, 14, 15) cubone too
Choice Band Diglett Earthquake vs. Larvitar: 40-48 (181.8 - 218.1%) -- guaranteed OHKO
(40, 41, 41, 42, 42, 43, 43, 44, 44, 45, 45, 46, 46, 47, 47, 48) not gonna be living that anytime soon lol
Choice Band Diglett Rock Slide vs. Gastly: 13-16 (68.4 - 84.2%) -- guaranteed 2HKO
(13, 13, 13, 14, 14, 14, 14, 14, 14, 15, 15, 15, 15, 15, 15, 16) lol gas the diggy check
Choice Band Diglett Earthquake vs. Kabuto: 32-38 (168.4 - 200%) -- guaranteed OHKO
(32, 32, 33, 33, 33, 34, 34, 34, 35, 35, 36, 36, 36, 37, 37, 38) kabuto is a thing????
Choice Band Diglett Double-Edge vs. Exeggcute: 14-17 (63.6 - 77.2%) -- guaranteed 2HKO
(14, 14, 14, 14, 15, 15, 15, 15, 15, 15, 16, 16, 16, 16, 16, 17) eggy is p good "check" (because literally nothing hasn't been ohkoed or 2hkoed yet)
Choice Band Diglett Double-Edge vs. Koffing: 10-12 (47.6 - 57.1%) -- 80.9% chance to 2HKO
(10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 12) 36/236+ is what i calced but
Choice Band Diglett Double-Edge vs. Koffing: 10-12 (43.4 - 52.1%) -- 6.6% chance to 2HKO
(10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 12) with 196/236+ oh and it cant be trapped so koffing is prolly best check in meta
Choice Band Diglett Rock Slide vs. Ledyba: 54-64 (270 - 320%) -- guaranteed OHKO
(54, 55, 55, 56, 56, 57, 58, 58, 59, 60, 60, 61, 62, 62, 63, 64) completions sake
Choice Band Diglett Earthquake vs. Oddish: 20-24 (90.9 - 109%) -- 56.3% chance to OHKO
(20, 20, 20, 21, 21, 21, 21, 22, 22, 22, 22, 23, 23, 23, 23, 24) idk what this runs lol
Choice Band Diglett Earthquake vs. Clamperl: 16-19 (80 - 95%) -- 68.8% chance to OHKO after 2 layers of Spikes
(16, 16, 16, 16, 16, 17, 17, 17, 17, 17, 18, 18, 18, 18, 18, 19) dk what this runs either
Choice Band Diglett Earthquake vs. Onix: 20-24 (95.2 - 114.2%) -- 81.3% chance to OHKO
(20, 20, 20, 21, 21, 21, 21, 22, 22, 22, 22, 23, 23, 23, 23, 24) this is 76/236+ onix, base 160 def, still an ohko
Choice Band Diglett Earthquake vs. Trapinch: 20-24 (86.9 - 104.3%) -- 81.3% chance to OHKO after 1 layer of Spikes
(20, 20, 20, 21, 21, 21, 21, 22, 22, 22, 22, 23, 23, 23, 23, 24) 156/76 is what eren says this runs
Choice Band Diglett Double-Edge vs. Baltoy: 16-19 (69.5 - 82.6%) -- guaranteed 2HKO
(16, 16, 16, 16, 16, 17, 17, 17, 17, 17, 18, 18, 18, 18, 18, 19) eren's spread
Choice Band Diglett Earthquake vs. Bellsprout: 23-28 (109.5 - 133.3%) -- guaranteed OHKO
(23, 24, 24, 24, 24, 25, 25, 25, 26, 26, 26, 26, 27, 27, 27, 28) idk what this runs so calced with 0/0
Choice Band Diglett Earthquake vs. Duskull: 13-16 (61.9 - 76.1%) -- guaranteed 2HKO
(13, 13, 13, 14, 14, 14, 14, 14, 14, 15, 15, 15, 15, 15, 15, 16) used spread from that spikes team on page 1
-1 Choice Band Diglett Earthquake vs. Growlithe: 22-26 (88 - 104%) -- guaranteed OHKO after 1 layer of Spikes
(22, 22, 22, 22, 23, 23, 23, 23, 24, 24, 24, 24, 25, 25, 25, 26) 236/236+
Choice Band Diglett Double-Edge vs. Lotad: 21-25 (105 - 125%) -- guaranteed OHKO
(21, 21, 21, 22, 22, 22, 22, 23, 23, 23, 23, 24, 24, 24, 24, 25) idk what this runs or why its c rank
Choice Band Diglett Earthquake vs. Mankey: 22-27 (104.7 - 128.5%) -- guaranteed OHKO
(22, 23, 23, 23, 24, 24, 24, 24, 25, 25, 25, 25, 26, 26, 26, 27) dont think these run bulk so i have 36/76 in calc
Choice Band Diglett Earthquake vs. Poliwag: 22-27 (104.7 - 128.5%) -- guaranteed OHKO
(22, 23, 23, 23, 24, 24, 24, 24, 25, 25, 25, 25, 26, 26, 26, 27) not today
Choice Band Diglett Earthquake vs. Rhyhorn: 25-30 (92.5 - 111.1%) -- 68.8% chance to OHKO
(25, 25, 26, 26, 26, 27, 27, 27, 27, 28, 28, 28, 29, 29, 29, 30) 196/236+ gets guaranteed ohko after 1 spike
Choice Band Diglett Rock Slide vs. Anorith: 17-20 (77.2 - 90.9%) -- guaranteed 2HKO
(17, 17, 17, 17, 17, 18, 18, 18, 18, 18, 19, 19, 19, 19, 19, 20) anorith is surprisingly bluk
Choice Band Diglett Earthquake vs. Azurill: 20-24 (95.2 - 114.2%) -- 81.3% chance to OHKO
(20, 20, 20, 21, 21, 21, 21, 22, 22, 22, 22, 23, 23, 23, 23, 24) 0/116
Choice Band Diglett Earthquake vs. Carvanha: 30-36 (142.8 - 171.4%) -- guaranteed OHKO
(30, 30, 31, 31, 32, 32, 32, 33, 33, 33, 34, 34, 34, 35, 35, 36) didnt even bother calcing any spreads other than 0/0 because carv is frail af
Choice Band Diglett Earthquake vs. Drowzee: 22-27 (88 - 108%) -- 50% chance to OHKO
(22, 23, 23, 23, 24, 24, 24, 24, 25, 25, 25, 25, 26, 26, 26, 27) 196/0 i dont really know what this mon runs, the only thing i know about it is one time the viability rankings wasted like one and a half pages on this shit
Choice Band Diglett Earthquake vs. Houndour: 52-62 (247.6 - 295.2%) -- guaranteed OHKO
(52, 53, 53, 54, 55, 55, 56, 57, 57, 58, 58, 59, 60, 60, 61, 62) completions sake
Choice Band Diglett Earthquake vs. Magby: 47-56 (223.8 - 266.6%) -- guaranteed OHKO
(47, 48, 48, 49, 49, 50, 50, 51, 52, 52, 53, 53, 54, 54, 55, 56) " diggy only takes ~30% from mach
Choice Band Diglett Earthquake vs. Smoochum: 30-36 (142.8 - 171.4%) -- guaranteed OHKO
(30, 30, 31, 31, 32, 32, 32, 33, 33, 33, 34, 34, 34, 35, 35, 36) "
Choice Band Diglett Rock Slide vs. Spinarak: 22-26 (95.6 - 113%) -- 75% chance to OHKO
(22, 22, 22, 22, 23, 23, 23, 23, 24, 24, 24, 24, 25, 25, 25, 26) is p good for a thot, running aerow's sexy spread